ELECTROLYSIS APPARATUS

Abstract

A device for electrolytic production of hydrogen and oxygen, comprising: process lines for feed of water and electrolyte and withdrawal of the electrolysis products, an electrolyser, comprising a body with upper and lower covers made of electrically conducting material, short-circuited electrodes, one of which is located centrally in the electrolyser, and the other is formed by the inside surface of the body, and an electromagnetic system, comprising magnets, mounted above the upper and under the lower covers of the body, the electrolyser being rotatable relative to the magnets.

Description

BACKGROUND OF THE INVENTION

This invention relates to the area of electrochemistry, namely to designs of electrolysers for the production of hydrogen and oxygen by the electrolysis of water.

There is a known installation for electrolysis of water in a centrifugal field (Russian patent 2253700, publ. Jun. 10, 2005), comprising process lines for feed of water and starting electrolyte and withdrawal of the electrolysis products, an electrolyser, consisting of a current-conducting body, upper and lower covers and electrodes, one of which is mounted on a vertical shaft connected to a rotary drive, said shaft having channels for supplying electrolyte solution into the body of the electrolyser and for withdrawing the electrolysis products, and the other is formed by the inside surface of the body of the electrolyser. The installation is equipped with a device for transformation and distribution of electrical energy with an external electric circuit, connected electrically to the rotary drive of the shaft. The electrolyser is equipped with a device for distribution of the stream of circulating electrolyte solution, constructed from electrically-insulating material and located above the shaft-mounted electrode, current supply and two stationary sliding contacts, connected to the device for transformation and distribution of electrical energy. The drawback of the known installation is intensive wear of the brushes at high rotary speeds of the electrolyser. Moreover, the brush contacts introduce additional resistance into the electric circuit of the electrolyser, which hampers the electrolysis process. Furthermore, the magnitude of the current passing through the brush contacts is limited.

The document “Installation for decomposition of water by electrolysis” (Russian patent 2224051, publ. Feb. 20, 2004) describes apparatus having process lines for feed of water and electrolyte and withdrawal of the electrolysis products, an electrolyser, comprising a body mounted on a shaft connected to a rotary drive, said shaft having channels for supply of electrolyte solution and withdrawal of the electrolysis products, a channel for withdrawal of the electrolyte solution, short-circuited electrodes, one of which is located on the shaft, and the other is formed by the inside surface of the body, and a heat exchanger, as well as upper and lower bearing units, in which the shaft is positioned vertically. The external circuit for circulation of electrolyte solution contains an annular chamber of electrolyte solution with inside surface in the form of a helix, fixed in the upper bearing unit, a sensor for presence of electrolyte solution and a mixer of the electrolyte solution, connected to the lines for feed of electrolyte and water and the channel for supply of electrolyte solution, the body of the electrolyser is constructed from current-conducting material and is provided with lower and upper covers made of current-conducting material, a channel for withdrawal of electrolyte solution is provided in the upper cover and is equipped with a control valve, communicating with the annular chamber of electrolyte solution, the inside surface of the body is provided with at least one guide groove, the line for feed of water is equipped with a device for controlling water consumption, the line for withdrawal of the electrolysis products is equipped with a device for pumping out the electrolysis products, the heat exchanger is located in the external circuit for circulation of electrolyte solution, and the sensor for presence of electrolyte solution is connected to the device for controlling water consumption and the rotary drive of the shaft. The drawbacks of the known installation include the need for high working speeds of rotation of the electrolyser, which makes the device rather unsuitable for industrial use. Other drawbacks include complexity of design, and low productivity.

Embodiments of the present invention may have the advantages of simplification of design, decrease in working speed of rotation of the electrolyser and increase in productivity.

SUMMARY OF THE INVENTION

One or more of the above problems may be solved in that the known device for electrolytic production of hydrogen and oxygen, containing process lines for feed of water and electrolyte and withdrawal of the electrolysis products, an electrolyser, comprising a body with upper and lower covers made of electrically conducting material, mounted on a shaft connected to a rotary drive, said shaft having channels for supply of electrolyte solution and withdrawal of the electrolysis products, short-circuited electrodes, one of which is located on the shaft, and the other is formed by the inside surface of the body, moreover the line for withdrawal of the electrolysis products contains, connected in series, a device for pumping out the electrolysis products and a separator, and the line for feed of water and electrolyte contains tanks for water and electrolyte, a device for controlling water consumption, valves, mixer and heat exchanger, it is equipped with an magnetic (optionally electromagnetic) system, comprising a number of fixed permanent magnets or electromagnets in the form of disks (or other shapes or cross-sections), mounted with opposite poles in parallel above the upper cover and under the lower cover of the body, a magnetic circuit, in the case of electromagnets, connected mechanically to them, with an exciting winding connected electrically to a pulse generator and a voltage transformer, on the line for withdrawal of the electrolysis products there is a gas analyser, the inlet of which is connected to the outlet of the device for pumping out the electrolysis products, and the outlet is connected to the device for controlling the water consumption, moreover the short-circuited electrode located on the shaft is constructed in the form of a cylinder with radial channels.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 shows schematically an embodiment of the device; and

FIG. 2 shows a simplified plan view of an arrangement of magnets.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The installation shown in the drawing contains an electrolyser 1, comprising a cylindrical body or drum 2, made of electrically conducting non-magnetic material with upper 3 and lower 4 covers made of electrically conducting magnetic material, mounted on vertical shaft 5, made of current-conducting non-magnetic material, in upper 6 and lower 7 bearing units. Shaft 5 is connected to rotary drive 8 and on the inside it has channels for supply of electrolyte solution or water 9 and for withdrawal of the electrolysis products 10. On shaft 5 inside the electrolyser there is a short-circuited electrode 11 with radially positioned channels 12 (e.g. anode), made of electrically conducting non-magnetic material. The inside surface of body 2 forms the other electrode (e.g. cathode). The position of the interface between the anode and the cathode is preferably chosen to provide balanced surface areas for the release of the electrolysis products. The channel for feed of electrolyte solution or water 9 is connected to the line for feed of water and electrolyte 13, with heat exchanger 14, mixer 15, to valve 16, to electrolyte tank 17, to valve 18, to the device for controlling water consumption 19 and to water tank 20. The heat exchanger 14 is also connected to a drain valve 21. The channel for withdrawal of the electrolysis products 10 is connected via the process line for withdrawal of the electrolysis products 22 to the device for pumping out the electrolysis products 23, connected to gas analyser 24, electrically connected to the device for controlling water consumption 19 and to the separator 25 for separating the oxygen-hydrogen mixture into oxygen and hydrogen. The electrolyser is equipped with a permanent or electromagnetic system, comprising upper 26 and lower 27 fixed magnets (e.g. in the form of disks), and, for the electromagnetic option, magnetic circuit 28 connected mechanically to them, exciting winding 29, connected electrically to a controllable pulse generator 30 and to a controllable voltage transformer 31. The surfaces of the electrolyser in contact with the electrolyte are covered with special coatings, which improve the electrical properties of the electrically conducting parts and protect the materials from corrosion.

The device operates as follows. Electrolyte from electrolyte tank 17 goes via the process line for feed of electrolyte 13 through the open valve 16 into mixer 15, then into heat exchanger 14, and from there through the channel for feed of electrolyte solution 9, located on shaft 5, into electrolyser 1. Valve 18 on the water feed line is closed. Once the electrolyser 1 has been filled with electrolyte solution, valve 16 is closed and the rotary drive 8 of shaft 5 is switched on, causing electrolyser 1 to rotate, accelerating it until the start of the electrolysis process. Once the electrolysis process begins, the rate at which it continues will be expected to decrease due to conversion of water from the electrolyser 1 and the reduction of surface area available for the passage of electricity. Control of the output rate is effected by a signal from the gas analyser 24, which operates the device for controlling water consumption 19 through the process line for feed of water 13 into electrolyser 1. The installation goes into automatic mode for controlling the feed of water from water tank 20 through the device for controlling water consumption 19, the open valve 18, the mixer of electrolyte solution 15, heat exchanger 14 and the channel for feed of electrolyte solution 9 into electrolyser 1. In the rotating electrolyser 1, during production of hydrogen and oxygen the volume of the electrolyte solution and hence its concentration vary continually: the concentration of the electrolyte solution increases, and the volume decreases. Each of the electrodes in electrolyser 1 can perform the function of anode or cathode depending on the chemical composition of the electrolyte used.

During rotation, under the action of centrifugal force an artificial gravitational field is created in electrolyser 1, under the action of which the cations and anions in the form of hydrates, having substantially different intrinsic mass, are separated. The heavier ions, e.g. cations, form, near the inside surface of body 2 (cathode), a negative electric space charge, which induces an adequate charge of conduction electrons in body 2, made of current-conducting material. The light ions concentrate in the region between the cathode and anode 11, forming their own positive space charge, and if the magnitude of its potential is sufficient to create an electric field capable of deforming the hydrate shells of the light ions, the equilibrium that had been established will be disrupted on anode 11. The light ions will approach the surface of anode 11 and will be discharged. The heavy ions will also give up their charge to the cathode and a constant electric current will flow between the electrodes through the upper 3 and lower 4 covers and shaft 5, made of current-conducting materials, as in a short-circuited circuit. The ions of the electrolyte will be reduced, forming hydrogen and oxygen, and the electrolysis intermediates will enter into side reactions with the water. The reduced hydrogen and oxygen will be displaced towards the centre of electrolyser 1 and will be sent to the consumer in the form of oxygen-hydrogen mixture through the channel for withdrawal of the electrolysis products 10, the device for pumping out the electrolysis products 23 and gas analyser 24.

For separating the oxygen-hydrogen mixture into oxygen and hydrogen, the installation can be equipped with a separator 25, from which the separated gases are sent to the consumers of oxygen and hydrogen. In similar known devices the electrolysis process takes place under the action of a centrifugal field alone, which presupposes high angular frequencies of rotation of the electrolyser (3000-5000 radians per second). Technically this is difficult to accomplish. The proposed installation employs a magnetic system, which made it possible to lower the working angular frequencies of rotation of the electrolyser to (500-1500 radians per second) and increase the productivity of the electrolyser by a large factor.

By supplying the electromagnetic winding 29 from a controllable constant-voltage transformer 31, it is possible to act upon an electrically charged particle moving in a constant magnetic field with a force:

F=B·V·q,

where

• B is magnetic induction, TI;
• V is the linear velocity, m/s;
• q is the magnitude of the electric charge, K.

The vectors of the forces acting on the negative and positive particles are directed opposite and perpendicular to the vector of the linear velocity, so that the heavy ions go towards the periphery of the electrolyser, and the light ones go towards the centre.

Connection of the electromagnetic winding 29 to the controllable pulse generator 30 makes it possible to act additionally on the charged particles at the resonance frequency that promotes their separation. The frequency and relative duration of the generator pulses are selected in relation to the chemical composition of the electrolyte solution, so as to enter into resonance corresponding to the given electrolyte. By utilizing the resonance effect, further lowering of the working angular frequencies of rotation of the electrolyser and increase of its productivity become possible.

The process of decomposition of water into hydrogen and oxygen by reduction of their ions is accompanied by a decrease in enthalpy of the electrolyte solution, as a result of which the temperature of the solution falls continually, and if the heat losses are not compensated, the solution will freeze and the process will come to a halt. For this reason it is necessary to heat the solution. For this purpose, a heat exchanger 14 is installed in the process line for supply of water. Thermal energy can be supplied to heat exchanger 14 in the form of exhaust gases or antifreeze from an internal combustion engine or in some other form. To meet safety requirements the installation can be equipped with a protective casing. Transformation of mechanical, electrical and thermal energy to chemical energy takes place in the proposed device.

The gas analyser 24 used can be of the type AVP-02, or AKPN-02, also performing the function of sensor. An electric vacuum pump can be used as the device for withdrawal of the electrolysis products 24, with a TP-3R voltage transformer as the controllable voltage transformer 31, and a solenoid valve as the device for controlling water consumption 19.

FIG. 2 shows in plan view one suitable arrangement of the magnets. FIG. 2 shows a simplified view of the apparatus of FIG. 1 from the direction of arrow 40 of FIG. 1. In FIG. 2 the drum 2 of FIG. 1 is shown at 51 and the shaft 5 of FIG. 1 is shown at 52. The magnets 50 are located on the drum 51. The magnets are spaced evenly around the shaft 52, and are preferably located at equal distances therefrom. The magnets may be permanent magnets or electromagnets. Preferably, the magnets are arranged in pairs, so that diametrically opposite each magnet there is another magnet equally spaced from the shaft 52. Any suitable number of pairs of magnets may be used.

The proposed device makes it possible to increase the productivity of the installation, lower the working angular frequencies of rotation of the electrolyser and simplify the design. The device can be manufactured using traditional constructional materials, components and known electrolytes and can be used in units of internal combustion engines of means of transport, increasing their fuel economy, with steam turbines of thermal and nuclear power stations, for utilization of industrial heat in metallurgy etc.

The applicant hereby discloses in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. The applicant indicates that aspects of the present invention may consist of any such individual feature or combination of features. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention.

Claims

1. A device for electrolytic production of hydrogen and oxygen, comprising: the electrolyser being rotatable relative to the magnets.

process lines for feed of water and electrolyte and withdrawal of the electrolysis products,

an electrolyser, comprising a body with upper and lower covers made of electrically conducting material,

short-circuited electrodes, one of which is located centrally in the electrolyser, and the other is formed by the inside surface of the body, and

an electromagnetic system, comprising magnets, mounted above the upper and under the lower covers of the body,

2. A device as claimed in claim 1, wherein the electrolyser is mounted on a shaft connected to a rotary drive, said shaft having channels for supply of electrolyte solution and withdrawal of the electrolysis products.

3. A device as claimed in claim 1, wherein the opposite poles of the magnets are mounted in parallel.

4. A device as claimed in claim 1, wherein the magnets are in the form of disks.

5. A device as claimed in claim 1, wherein the line for withdrawal of the electrolysis products contains, connected in series, a device for pumping out the electrolysis products and a separator, and the line for feed of water and electrolyte contains tanks for water and electrolyte, a device for controlling water consumption, valves, a mixer and a heat exchanger.

6. A device as claimed in claim 1, wherein one or more of the magnets are electromagnets.

7. A device as claimed in claim 6, comprising a magnetic circuit connected mechanically to the magnets with an exciting winding, connected electrically to a pulse generator and a voltage transformer.

8. A device as claimed in claim 1, comprising a gas analyser on the line for withdrawal of the electrolysis products, the inlet of the gas analyser being connected to the outlet of a device for pumping out the electrolysis products, and the outlet of the gas analyser being connected to the device for controlling the water consumption.

9. A device as claimed in claim 1, wherein the short-circuited electrode located on the shaft is constructed in the form of a cylinder with radial channels.

10. A device as claimed in claim 1, wherein the magnets are configured for assisting the electrolysis of fluid in the electrolyser.