RU2149921C1 - Updating of electrolysis systems - Google Patents

Abstract

FIELD: chemistry. SUBSTANCE: cellular device has complex structure composed of separating discs, cellular plates of first type ( anode ), cellular plates of second type ( cathode ) and separating membranes. Joining conductive rods pass through holes in cellular plates to perform selective electric connection. Water and electrolyte for submersion of cellular plates are supplied through inlets holes. Normally membranes isolate adjacent plates-cathodes and plates-anodes from mixing released gaseous oxygen and hydrogen and provide for flow of ion current. EFFECT: enhanced efficiency of conversion of electric energy. 12 cl, 29 dwg

Description

 The present invention relates to the formation of gaseous hydrogen and gaseous oxygen from water, either as a mixture or as separated gases by an electrolysis process, and also relates to applications associated with the use of released gas. Embodiments of the invention, in particular, relate to a device for the efficient production of these gases and to the use of these gases as a heat source in atomic welding or cutting and to the elimination of gaseous losses.

A method of electrolyzing water in the presence of an electrolyte such as sodium hydroxide (NaOH) or potassium hydroxide (KOH) with the release of hydrogen and oxygen gases (H ₂ , O ₂ ) is well known. The process involves applying a DC potential difference between two or more anode / cathode electrode pairs and supplying the minimum energy required to break HO bonds (i.e., 68.3 kcal / mol under normal conditions). Gases are produced in a stoichiometric proportion for O ₂ : H ₂ in a 1: 2 ratio, allocated respectively at the anode (+) and cathode (-).

 The following articles may be cited: "Modern Electrochemistry, v. 2, John O'M. Bockris and Amulya KN Reddy, Plenum Publishing Corporation", "Electro-Chemical Science, J. O'M Bockris and DM Drazik, Taylor and Francis Limited "and" Fuel Cells, Their Electrochemistry, J. O'M. Bockris and S. Srinivasan, McGraw-Hill Book Company. "

 A discussion of experimental work in relation to electrolysis processes can be found in "Hydrogen Energy, Part A, Hydrogen Economy Miami Energy Conference, Miami Beach, Florida, 1974, edited by T. Nejat Veziroglu, Plenum Press".

 Particularly relevant are articles submitted by J. O'M. Bockris on p. 371-379, F. C. Lensen and F.H. Schubert on p. 425-439 and B. Pangborn and John C. Sharer on p. 499-508.

 By and large, the amount of gas released depends on a number of variables, including the type and concentration of the used electrolytic solution, the surface area of the anode-cathode electrode pair, electrolytic resistance (equivalent to ionic conductivity, which is a function of temperature), achievable current density, and potential difference between the anode and cathode. The total supplied energy should be sufficient for the dissociation of water ions and the formation of hydrogen and oxygen gases, however, it is necessary to avoid coating (oxidation / reduction) of the metallic or current-conducting non-metallic materials of which the electrodes are made.

 You can refer to the previous Australian Patent N 487062 by Yull Brown, which discloses the design of an electrolytic cell for the production of hydrogen and oxygen, as necessary, together with a safety device that prevents the creation of excessive pressure of the released gases. FIG. 2 in Brown's patent shows several electrodes (20a, 20b) with a series electrical connection between two terminals (22) to which a potential difference is applied. Cell (20) provides the volumetric flow rate of the gas at the outlet, and if this capacity is insufficient for a specific application, then a larger number of separate cellular devices are required, which are all electrically connected in series. The end result is a large design that needs to be supported.

 It is also not possible to achieve the required high volumetric gas flow rates (of the order of 10.000 l / h) from previously known devices without the use of expensive and complex equipment, but even then the equipment is characterized by low efficiency of electric energy conversion for the production of gaseous hydrogen and oxygen. Thus, the commercial use of devices of this type of large size is not economically feasible.

 Mixed gases hydrogen and oxygen (or hydroxy-gas) are used as a thermal source during combustion in a stream, for example in furnaces. Only one hydrogen is used for atomic cutting, and often for atomic welding, although the device described in Brown's patent performs atomic welding in the presence of mixed hydrogen and oxygen. Modern industrial practice has clearly confirmed that the presence of oxygen in the arc plasma causes intense oxidation of tungsten electrodes.

 One of the problems that occurred when using these applications is the need to combine an electrical switchgear in order to convert the supply voltage to an appropriate level for the block of electrolytic cells (i.e. by means of step-down transformers). The final completed design is inefficient, from an electrical point of view, and cumbersome, and can also be expensive if accurate voltage and current adjustment is required (hence, gas flow regulation).

Combustible hydrogen and oxygen gases mixed in a single stream burn at a very high temperature, usually of the order of 6000 ^° C. Hydrogen / oxygen welding devices are widely known and consist of a welding tip or a manual part with a double gas hose connected for separate supply of oxygen and hydrogen .

 There are four other known types of welding machines and methods for their use - oxygen-acetylene welding, electric arc welding, MIG (metal-inert gas) / TIG (tungsten-inert gas) systems and plasma cutting.

It is estimated that more than 100,000 oxygen-acetylene plants are in operation in Australia. Of these, approximately 70% is primarily used for cutting metals, and the remaining ones are used as heat sources for sheet metal fusion welding, brazing, silver brazing, etc. Oxygen-acetylene plants can usually weld metal from 0.5 to 2 mm thick. In addition, metal up to 140 mm thick can be cut, but only if the steel contains a high percentage of iron. The reason for this is that iron and oxygen are necessary to maintain the oxidation process, which causes the cutting effect. Gaseous acetylene creates an initial temperature for the start of the oxidation reaction, usually equal to 850 ^o C. Oxygen-acetylene plants require cylinders with gases (acetylene and oxygen), therefore, cylinders must be bought or rented and then kept in good condition and re-filled when use.

 Arc welding is a method used for welding metals more than 1.5 mm thick. The principle of operation is that the manual part is supplied together with the consumable electrode, and the working part forms another electrode. An alternating or direct current potential difference is created between the electrodes, thereby causing an arc to form when the manual part is brought into an area close to the working part. The arc can be used to melt or weld metal parts together.

 MIG (metal-inert gas) systems are based on a continuous wire feed system. In one known design, the sacrificial wire is surrounded by gaseous argon (or plasma), which is usually supplied from a cylinder. TIG (tungsten inert gas) systems, on the other hand, require a fused wire that must be manually entered into the weld area. MIG / TIG systems can weld metal from 1 to 20 mm thick, typical stainless steel, aluminum, mild steel, etc. References regarding the plasma MIG process can be made to the text "The Science and Practice of Welding, v. 2, A.C. Davies, Cambridge University Press".

Plasma cutting is a cutting method by supplying compressed air (containing mainly nitrogen) to a direct current electric arc, thereby creating very high temperatures (about 15,000 ^° C) and, thus, tearing electrons from nitrogen nuclei to form a high-temperature plasma. This plasma can be used to cut iron and iron materials such as mild steel, stainless steel, copper, brass and aluminum. Used plasma cutters can cut material up to 25 mm thick and have the advantage of not requiring a gas cylinder and using ordinary air. References for plasma cutting can be made to the text "Gas Shielded Arc Welding, NJ Henthorne and RW Chadwick Newnes Technical Books". As follows from the discussion of the prior art, no device or system can perform all the functions of welding and cutting, and usually one of the systems described above should be preferred to others for any particular work. This, in turn, requires metal workers or other industrial manufacturers of the metal industry to buy and maintain many different types of welding devices in order to be able to carry out any required work. The costs associated with buying gas for cylinder replacement are also very high.

 A preferred object of the present invention is to propose a structure by which gaseous hydrogen and oxygen can be produced by an electrolytic process that is free from one or more of the above-mentioned disadvantages. In this sense, the electrolytic device is compact and provides greater efficiency than previous devices, with comparable gas flow rates.

 Another preferred objective of the present invention is to provide an improved electrolytic cell structure for use in the production of hydrogen and oxygen gases. The electrolytic cell can be used in hydrogen / oxygen welding or hydrogen plasma cutting. Other applications may relate to industrial processes that require sources of combustible fuel, such as calcining furnaces, and to incineration of difficult-to-handle waste.

 Another preferred objective of the present invention is to propose the design of an electrolytic cell, which provides optional separation or mixing of gaseous hydrogen and oxygen into a single gas stream.

 The present invention further mainly aims to create a single welding unit that can satisfy all the requirements of the user for welding or cutting. The advantage is that no hydrogen or oxygen cylinders are required. No cylinders with any other gas, such as argon, are also required in MIG / TIG systems with immersion in an inert gas.

 Another preferred object of the present invention is to provide a back flame suppressor for hydrogen / oxygen welding or a tip for cutting with hydrogen plasma.

 Therefore, the invention discloses a cellular structure for electrolysis of water to release gaseous hydrogen and oxygen.

 This design contains a plurality of anode electrodes in a folded state, each anode electrode contains a flat plate through which one or more common first current-conducting connecting elements pass, and a plurality of cathode electrodes in a folded state, each cathode electrode contains a flat plate, through which one or more common second current-conducting connecting elements pass; in this design, the anode electrodes and the cathode electrodes overlap.

 The invention further discloses a cellular structure for electrolysis of water to release gaseous hydrogen and oxygen.

 The specified design contains many electrodes-anodes interconnected by one or more of the first common current-conducting elements connected electrically in parallel; anode electrodes overlapped by a plurality of cathode electrodes interconnected by one or more second common current-conducting elements connected electrically in parallel; said electrodes-anodes and electrodes-cathodes forming a cellular device and a plurality of cellular devices connected electrically in series.

 The invention further discloses a cellular structure for electrolysis of water to release gaseous hydrogen and oxygen.

 The specified design contains many electrodes-anodes combined in a folded design, each electrode-anode contains a flat plate through which passes one or more common first current-conducting connecting elements; a plurality of cathode electrodes combined in a linear spatial folded structure, each cathode electrode contains a flat plate through which one or more common second current-conducting connecting elements pass; in this design, the anode electrodes and cathode electrodes overlap; and many membranes, each membrane is located between the adjacent electrode-anode and the electrode-cathode, the membranes allow the ion current to pass between adjacent electrode-anodes and electrode-cathodes, but selectively block the passing gas flow depending on the pressure difference between opposite sides of the membrane.

 The invention further discloses an electrolytic device for releasing gaseous pollutants.

 The device comprises a plurality of anode electrodes overlapped by a plurality of cathode electrodes; a plurality of separation membranes between each adjacent electrode-anode and electrode-cathode; means for supplying at least water to the anode electrodes and cathode electrodes; said supply means must be operable to control the pressure difference of at least water on opposite sides of each membrane to provide optional separation or mixing of the released gaseous oxygen and hydrogen.

 The invention further discloses the design of a combustion device for utilizing the thermal decomposition of gaseous pollutants.

 The combustion device comprises a hemispherical combustion chamber; the supply of hydrogen and oxygen gases to the combustion chamber through a winding path exiting through a plurality of concentrically arranged nozzles directed to the epicenter of the hemispherical chamber; an inlet for supplying gaseous pollutants; In a combustion device, gaseous pollutants are burned together with gases (hydrogen and oxygen).

 The invention also discloses a multi-module welding and cutting generator comprising a power source adapted to provide a plurality of output voltages of alternating and direct current; an electrolytic device connected to a power source intended for the production of optionally hydrogen and oxygen individually or as a mixture of hydrogen and oxygen by electrolysis of water using a constant voltage supplied from the power source; hydrogen, oxygen and mixed hydrogen and oxygen together with output voltage sources suitable for connection to welding and / or cutting equipment.

 The invention also discloses a backfire suppressor for a welding tip used in gas combustion, the suppressor contains a grid barrier to the flow of gases to be burned, the grid barrier has openings to allow free passage of gases, but to prevent the passage of the back flame, the back flame is not having the ability to pass the barrier is thus extinguished.

 FIG. 1a and 1b are a plan view and a side view of one mesh plate, respectively.

 FIG. 2 depicts a folded set of mesh plates.

 FIG. 3 shows a vertical section of a block of electrolytic cells.

 FIG. 4 is a vertical sectional view showing the construction of electrodes of a part of another block of electrolytic cells embodying the invention.

 FIG. 5 is a perspective view of a portion of one electrode shown in FIG. 4.

 FIG. 6 is a simplified representation of the construction of the sequence of electrodes shown in FIG. 4.

 FIG. 7a and 7b depict the mechanical connection of one group of cells in another embodiment.

 FIG. 8 shows the connection of several groups of cells shown in FIG. 7a and 7b.

 FIG. 9 shows a series electrical connection of several groups of cells in a block of cells.

 FIG. 10a and 10b depict the mechanical structure of the cell block device.

 FIG. 11a and 11b depict yet another embodiment of a mesh plate.

 FIG. 12a and 12b depict complementary cell plates for those depicted in FIG. 11a and 11b cells.

 FIG. 13 depicts details of perforation and portions of the mesh plates of FIG. 11a, 11b, 12a and 12b.

 FIG. 14 shows, in a break, the folded structure of the mesh plates of FIG. 11a, 11b, 12a and 12b.

 FIG. 15a is a schematic view of the gas separation system of FIG. fourteen.

 FIG. 15b is a stylized representation of FIG. 15a.

 FIG. 15c is an electrical equivalent circuit of FIG. 15a.

 FIG. 16 depicts a gas collection system for use with the cell block separation system of FIG. 14 and 15a.

 FIG. 17 is a cross-sectional view of a hydraulic scrubber and a stop valve.

 FIG. 18 is a cross-sectional view of a welding tip used with the equipment shown in FIG. 10, including back flame suppressor.

 FIG. 19a and 19b show a combustion decomposition furnace of polluting gases.

 FIG. 20 is a block diagram of a multi-module welding and cutting device.

 FIG. 21 is a diagram of the device of FIG. 20.

 DETAILED DESCRIPTION OF THE INVENTION

 The electrolytic cell block embodying the invention consists of several hexagonal-shaped electrolytic cell plates 10, one of which is shown in plan in FIG. 1a and in a side view in FIG. 1b. Each plate 10 has three slots 12, each of which is located on the alternating extreme sides of the plate 10. The other sides of each mesh plate 10 are provided with a conductive bridge or flange 14. Typically, twenty separate mesh plates 10 are combined to form one filled cell 16, as shown in a side view in FIG. 2. The total number of plates may vary in accordance with the required surface area and therefore is also a function of the diameter of the plate.

The combination in a set of neighboring mesh plates 10 is carried out in a different order so that the conductive bridges 12 of the neighboring plates protrude in opposite directions and with a relative rotation of 60 ^o . The indicated rotation is due to the fact that adjacent plates 10 must be of opposite polarity. The conductive bridges 14 are long enough to pass through the corresponding groove 12 in the adjacent board 10 without contacting this board and so as to contact the next successive plate, forming a conductive path between each alternating plates. Thus, the filled mesh structure 16 has three positive terminals and three negative terminals, although FIG. 2 depicts only two positive terminals and one negative terminal. The mesh set 16 is surrounded by an insulating body 18 (shown in torn form). The mesh plates 10 shown in FIG. 1a, 1b and 2 are suitable for forming a parallel electrical connection with each two adjacent mesh plates 10, forming either an anode or cathode.

 Parallel-layered flat mesh plates are described in Australian Patent N 487062. In it, a set of twenty mesh plates typically requires a potential difference between the individual electrodes of each mesh plate in the range of 1.55-2.0 V to release hydrogen gas and oxygen from water containing electrolyte from the usual 15% sodium hydroxide solution.

 FIG. 3 shows in vertical section seven filled cell sets 16 assembled in a hexagonal matrix and closed by a steel body 20, thereby forming a block of electrolytic cells 25. The cell sets 16 are isolated from the steel body 20 by nylon insulating inserts 22. The electrical interconnection of the individual cell sets 16 is not shown , but usually the cells are interconnected by their respective positive (+) and negative (-) terminals using tapes to form a serial connection.

 Sometimes it happens that a parallel interconnection of the mesh sets 16 is made. The actual electrical interconnection will depend on the number of individual mesh plates 10 constituting each mesh set 16, the supplied voltage and the current that must flow from the source.

 During the electrolytic reaction, when gaseous hydrogen and oxygen are released, water is consumed. 1 liter of water produces 1860 liters of mixed oxygen and hydrogen under normal conditions (n.o.) in the volume ratio indicated above. In the design shown, water is constantly supplied through the inlet 24.

 The nylon coating 18 separating adjacent sets facilitates the upward direction of the rising released gases, which must be collected using the gas outlet 26 located at the top of the cell block 25. Due to the volume expansion of 1: 1860, the released gases are self-compressible when they exit from the outlet 26 into a connecting pipe (not shown), which has a much narrower section than the cell block.

 FIG. 4 is a vertical section showing the mechanical structure of an electrolytic cell in accordance with the following embodiment. The main cellular device 30 is formed by the corresponding halves of the pair of overlapping electrodes 32, 34, located similar to overlapping ridges. Each electrode is formed by means of conductive holders 36, 38, usually made of resin bound graphite, mild steel or conductive polymers, eleven fingers 40, 42 in the form of fingers, also made of graphite, steel or conductive polymer, extend from the holders.

 FIG. 5 is a perspective view of one of the electrodes 32, in which the holder 36 and the plate 40 are rectangular in shape. It is not necessary that the electrodes have the indicated shape, but rather can take many other forms, an example of one of which will be described. A common requirement for all such structures is that the plates are parallel and connected by a common structural element orthogonal to the plates.

 Each pair of electrodes 32, 34 is arranged in an alternating structure such that the corresponding outermost plates 40a, 42a are approximately half offset about the total length of each electrode 32, 34. The corresponding middle plates are indicated by 40b and 42b.

 FIG. 6 depicts a folded structure in a simplified form. Each sixth plate is located in the space formed by the first and eleventh plates of the respective adjacent opposite electrodes.

 Referring again to FIG. 4, which depicts two filled mesh devices 30 and parts of subsequent corresponding neighboring mesh devices. The total number of cellular devices is determined by a constant voltage source, because a minimum anode / cathode voltage is required to start the electrolytic process, and each neighboring cellular device is in series electrical connection of parallel plates 40, 42. During the electrical process, cells 30 are immersed in water and electrolyte, a constant voltage is applied between the end plates 40c and 42c, forcing elementary ion currents (some of which are represented by dashed lines) kami) to flow between adjacent plates 40, 42, and the total current - along the respective holders 36, 38 and plates 40, 42 (shown by solid arrows). In each middle plate, currents of different directions are caused. For example, direct current flows from one terminal mesh plate 42a through the electrolyte, flowing through the middle plate 40b, and again through the electrolyte to the next terminal mesh plate 42a. This process causes a net positive charge to accumulate on one side of the middle plate 40b and a negative charge on the other side.

 The flow of ion current is accompanied by the dissociation of water molecules so that gases oxygen and hydrogen are produced respectively on the surfaces of the anode plate and cathode plate. The surfaces of the cathode plates are those plates to which the ion currents are directed. The converse is true for the surfaces of the anode plates.

 The voltage applied to the outermost plates 40c is divided evenly between the composite mesh devices 30, and the same applied voltage is equally divided between the corresponding outermost plates and the middle plates 40a and 42b, 40b and 42a.

 The achievable current density is limited, in particular, by the effective electrical resistance of the electrolytic solution. The smaller the distance between adjacent plates 40, 42, the lower the resistance. The overlapping design of the electrodes 32, 34 means that there is a large surface area per unit volume, and there is a minimum distance between the plate electrodes throughout the device. In this case, the resistance of the electrolyte remains low, therefore, the efficiency of converting electrical energy into the production of hydrogen and oxygen is greater than in previous designs.

 Due to the specific construction shown, it is not necessary to isolate each individual mesh device 30 from the same neighboring devices. The ion current flows naturally along the path of least resistance, therefore, shorter circuits between the cellular devices 30, but having a higher resistance, are avoided. Therefore, a large number of cells can be combined into an extended linear design and direct connection to a rectified voltage source is allowed, thus avoiding the need to electrically connect groups of cellular devices by pulling, as was done in previous developments.

 Each individual cellular device 30 satisfies the working conditions from the point of view of supplying voltage, surface area of the plates, etc., for the successful electrolysis of water, and as a result it works substantially independently of neighboring cellular devices 30.

Testing found that for a temperature range of 90 to 50 ^o C, a DC voltage in the range of 1.47-1.56 V applied to one cellular device 30 (i.e., one (half) of the whole electrode 32 or 34) requires a minimum (and optimal) density anode current of 0.034 A / cm ² to obtain a gas flow rate of about 340-300 l / h per 1 kW • h, respectively. The discovery that the minimum plate surface area corresponds to the optimal gas flow rate means that the total occupied volume can be kept minimal. For example, a rectified mains voltage of 240 V _SQ (rms) nominally leads to an average constant voltage of 215 V, therefore, when connecting directly to the device through a rectifier (i.e. without the required step-down transformer), a total of 140 cells are required. It is especially advantageous that equipment is not required for voltage conversion in terms of equipment cost, technical simplicity and loss avoidance.

 FIG. 7a is a partial torn side view of a mesh device 50 in accordance with another embodiment. The mesh device 50 is similar in configuration to the device shown in FIG. 4, except for the number and shape of the overlapping protruding elements and the shape of the electrode plates.

 FIG. 7b is a rear view of the mesh device 50 and, in particular, of the latest board 52c. The plate electrodes 52, 54 are in the shape of a hexagon. Through each plate 52, 54 are six connecting rods 56, 58, one near each vertex. Each of the alternating rods 56 is a common positive conductor, and the other set of alternating rods 58 are negative conductors. Each adjacent plate 52, 54 is electrically connected to either positive conductors or negative conductors. Intermediate liners 60 are inserted between adjacent plates 52, 54 for electrical insulation and for the formation of a space in which water and electrolyte circulate. The connection of each conductor 56, 58 to the corresponding plate electrode 52, 54 is usually carried out by tightening the nut or tight fit. The reason for connecting each plate 52, 54 to the three common conductors 56, 58 is to achieve a uniform current distribution over the entire surface area of the plate 52, 54.

 As can be seen in FIG. 7b, the positive conductor 56 exits from one end of the device for series connection with another set of cells, as well as the three negative protruding conductors 58 from the other end. All unconnected ends of the conductors are covered by non-conductive plugs 62.

 FIG. 8 depicts in a stylized form three cellular devices 50 connected electrically in series (connected in the longitudinal direction), and in particular the passage of protruding conductors 56, 58. The cellular devices 50 are placed in an insulating pipe 64, usually made of polyvinyl chloride (PVC), which has access for water exchange for immersion of plates 52, 54 and for removal of produced gases.

 FIG. 9 depicts a series electrical connection of several cellular devices 50 connected directly to a direct current output of an AC to DC converter (such as a simple rectifier using a diode bridge) without using a step-down transformer.

 FIG. 10a is a rear view of a mechanical structure of seven devices (labeled AG), each consisting of three series-connected mesh devices 50 (as shown in FIG. 8), forming a common mesh structure 70. The mesh devices 50 are in a steel cylinder 72 containing water and electrolyte required for the production of hydrogen and oxygen gases. Each group (A-G) of three mesh devices 50 is connected by a first group of steel connecting ties 74 at one end and a second group of steel connecting ties 76 (not shown) at the other end to form a jumper between the groups. Although in FIG. 10a shows a single first coupler 74, both sets of couplers are more clearly shown in FIG. 10b, which is an expanded side view of the groups A-G.

 The PVC pipes 64 shown in FIG. 10a, isolate adjacent groups in order to avoid the effect of a short circuit between them. The cellular structure 70 is very compact and, compared to the known Brown design, occupies only one third of its physical volume with a comparable gas volumetric flow rate, while also reducing the total mass in approximately the same ratio. The water supply for the electrolytic process is carried out through the inlet 78 located at the bottom of the cylinder 72, with the output of the obtained gas through the outlet 80 located at the top of the cylinder 72.

 The electrical connection to the terminal of the DC source is through a set of cells, and in this design, the connection is made to the central terminal 82 on the lower side of the cell A and to the central terminal 84 on the upper side of the cell G, respectively.

 FIG. 11a and 12a are a rear view of a further embodiment of the honeycomb plates 90, 98 of the first and second types. FIG. 11b and 12b are partial cross-sections along respective midlines, as shown in the drawing. General numbering is used where reference is required. Plates 90, 98 may perform the function of either an anode (+) or a cathode (-), as will become apparent later. Each plate contains a disk electrode 92, which has apertures (perforations) 96 of a hexagonal shape. Disc 92 is made of steel or tarred graphite or a conductive polymer material. The disk 92 is located in an annular rim or sleeve 94. The function of the holes 96 is to maximize the surface area of the disk electrode 92 and reduce the weight of the solid structure to 45%.

For example, for a disc with a diameter of 280 mm, the thickness of the disc should be 1 mm so that the current density (which varies between 90A / 2650 cm ² - 100 A / 2940 cm ^{2 of the} anode or cathode) is optimal. If the plate diameter is increased, which accordingly increases the surface area, it is necessary to increase the plate thickness in order to maintain the same conductivity for the desired current density.

 The distance between the planes of hexagonal holes (perforations) in a 1 mm thick disk is 2 mm, and the holes are 1 mm from the next adjacent hole in order to maintain the same total surface area as in previous designs and to optimize current density . Between adjacent hexagonal holes a distance of 1 mm is required (from plane to plane), as a smaller distance leads to thermal (resistive) losses, and a larger distance leads to an increase in the total weight of the plate.

 The annular rim 94 is made of PVC material and combines many holes 100, 102 with axes located at the same distance. The holes are intended for the passage of the connecting axes present in the assembled structure of the plates 90, 98 and forming a common conductor for the corresponding anode or cathode plates, as well as in the design of the device shown in FIG. 7a and 7b. The next two upper holes, 104, 106, each support a conduit for the flowing oxygen and hydrogen, respectively. The holes 108, 110 in the lower part of the annular rim 94 are intended for the inlet of water and electrolyte to the corresponding mesh plates 90, 98.

 FIG. 13 is an enlarged view of a portion of the mesh plate 90 shown in FIG. 11a. The hole 104 is connected to the hexagonal holes 96 inside the annular rim 94 by means of an internal channel 112. A similar design exists for the other hole 106 and for the water / electrolyte holes 108, 110.

 In the case where the released gases, hydrogen and oxygen must be kept separate (i.e. should not be obtained as a mixture), it is necessary to separate them upon receipt. In previous designs, this was achieved by using diaphragms that block the passage of gases and effectively isolate water / electrolyte on each side of the diaphragm. The ion transport is thus facilitated by the ionic permeability of the diaphragm material (i.e., the water – diaphragm – water path). This leads to an increase in ionic resistance and, consequently, to a decrease in efficiency. The previous patent N 487062 describes another design (see Fig. 6 therein), which uses magnets to separate gases.

 FIG. 14 depicts a torn-off assembly of four mesh plates in which two (anode) mesh plates 90 and two (cathode mesh plates 98) comprising it alternate. The two outermost discs in the assembled mesh plate design complete the formation of one mesh device 125. Between each adjacent spacers 116 made of polytetrafluoroethylene (PTFE) are arranged by plates 90, 98. Although not shown in Fig. 14, the cellular device contains separate gas pipes for hydrogen and oxygen, which respectively pass through the assembled structure of the honeycomb plates through the holes 106, 104, respectively. Gas pipelines for supplying water / electrolyte are arranged in a similar manner, passing respectively through the holes 108, 110 in the lower parts of the respective plates 90, 98.

 Only two pairs of anode / cathode mesh plates are shown. The number of such plates in a single mesh device 125 can be significantly increased.

 Also not shown are connecting current-conducting axes that electrically couple alternating common mesh plates. The reason for making large diameter holes in one mesh plate and making smaller holes in the next adjacent mesh plate is because the connecting axis will pass through larger holes without electrical connection (i.e., insulated with PVC pipes), but only forming electrical connection between alternating (common) mesh plates.

 Cellular device 125 is shown in FIG. 14 in a torn form. Assembled, all elements are assembled to obtain close contact. Mechanical fixation is achieved using one of two binders (adhesives), such as (a) PUR-FECT LOK (TM) 34-9002, which is a urethane reactive hot melt adhesive with the main component Methylene Bispheny / Dirsocynate (MDI) and b ) "MY-T-BOND" (TM), which is a solvent based PVC binder. Both binders are resistant to sodium hydroxide (20% presence in the electrolyte). In this case, water / electrolyte is located only in the area not occupied by the annular rim 94 of the mesh plate. Thus, the path for water / electrolyte is only the path from the inlet through the lower channels 118, 122, and for the removal of gases the path is only along the upper channels 112, 120. In the system designed and tested by the inventor, the thickness of the mesh plates 90, 98 was equal to 1 mm (2 mm along the edge due to the PVC ring rim 94), and the diameter is 336 mm. The mesh device 125 is separated from the next cell by means of an insulating separation disk 114 made of PVC. The separating disk 114 is also located at the beginning and end of the whole mesh bank.

 If it is not required to control the separation of the released gases, then the PTFE membrane 116 is absent.

 PTFE membrane 116 is fibrous and has gaps ranging in size from 0.2 to 1.0 microns. A suitable type is the Catalog Code J. type supplied by Tokio Roshi International Inc. (Advantec). Water / electrolyte fills the gaps, and the ion current flows only through water - there is no compensation for the flow of ions through the PTFE material itself. This leads to a decrease in resistance to ion flow. The PTFE material also has a “foaming point”, which is a function of pressure, therefore, by controlling the relative pressure on either side of the PTFE separation sheets, gases can be “forced through” the gaps to form a mixture or, conversely, to maintain separation. Other advantages of this design are significantly lower construction costs, improved operational efficiency and significantly greater fault tolerance.

 FIG. 15a is a stylized and broken-up schematic view of a linear connection of three series-connected mesh devices 125. For clarity, only six connecting axes 126-131 are shown. Axes 126-131 pass through the corresponding axial holes 102, 100 in various mesh plates 90, 98 in a folded structure. The polarity of the power connected to each open end axes to which the DC source is connected is also indicated. Axes 126-131 do not extend over the entire length of the three mesh units 125. This design is similar to that shown in FIG. 7a and 8. One third of the total voltage of the DC source is present on each pair (anode-cathode) of the mesh plates 90, 98.

 The following also shows gas pipelines 132, 133 for hydrogen and oxygen, respectively, which pass through the openings 104, 106 in the cellular plates 90, 98. Similarly, water / electrolyte pipelines 134, 135 passing through the openings 108, 110 in the cellular plates are shown.

 FIG. 15b separately shows how the relative potential difference changes in the middle mesh block 125. That is, the plate electrode 90a here functions as a cathode (i.e., relatively more negative) to produce hydrogen, and the plate electrode 98a here functions as an anode (i.e. e. relatively more positive) for oxygen production. This is the case for each alternating mesh device. Shown in FIG. 15b, arrows indicate circuits for electron and ion currents. FIG. 15c is an equivalent circuit diagram of FIG. 15b, in which the resistive elements are ionic resistance between adjacent anode-cathode plates. Thus, it can be seen that the cellular devices are connected in series.

 Due to a change in the function of the honeycomb plates 90a and 98a, additional gases are released on each of them, therefore, the corresponding channels 112 are connected to the opposite gas lines 132, 133. In particular, this can be achieved by simply rearranging the plates 90, 98.

 FIG. 16 depicts three mesh devices 125 shown in FIG. 15a connected to a gas collection device. Cellular devices 125 are located inside the reservoir 140, which is filled with water / electrolyte to the level indicated by h. Water is consumed during the electrolytic process, and its new supply is through the inlet 152. The water / electrolyte level h can be seen through the transparent glass 154. During normal operation, various flows of hydrogen and oxygen are produced and pass from the cellular device 125 to the corresponding elevated columns 142, 144 That is, the pressure of the electrolyte on opposite sides of the PTFE membrane 116 is equalized, so the gases cannot mix.

 Columns 142, 144 are also filled with water / electrolyte, and when it is consumed on the electrode plates, the electrolyte is again fed through circulation through water / electrolyte pipelines 134, 135. The circulation is caused by entrainment of the released gases and the circulating piping and column structures.

 The upper part of the reservoir 140 forms two gas cleaning columns 156, 158, respectively, for collecting hydrogen and oxygen gases. Gases rise up through the respective columns 142, 144 and exit the columns through openings at a point located within the overlapping partitions 146. This point where the gases exit the columns 142, 144 is below the water level h, which serves to eliminate any turbulent flow and gas trapped electrolyte. Partitions 146 located above level h purify the gas of any electrolyte trapped in the gas, and the purified gas is then exhausted through the respective outlet columns 148, 150 and, thus, into the gas receiver. The level h in the reservoir 140 can be adjusted by any conventional means using a float switch with fresh water supplied through the inlet pipe 152.

 The released gases will always separate from the water / electrolyte solution due to the difference in densities. Due to the relative height of the corresponding set of partitions and because of the difference between the densities of the gases and water / electrolyte, it is not possible to mix the released hydrogen and oxygen gases. The presence of a full volume of water inside the reservoir 140 keeps the mesh plates submerged and also serves to absorb shock from any internal detonations, if any.

In the case where gas mixing is required, two valves 136, 137 are firstly closed, located respectively in the pipeline 132 for the release of gaseous oxygen and the inlet 134 for water / electrolyte. This blocks the exit path for gaseous oxygen and causes the inlet water / electrolyte to pass into the inlet pipe 134 through the unidirectional stop valve 139 and pump 138. The water / electrolyte inside reservoir 140 is pressurized due to its depth (volume), and pump 138 works to increase pressure water / electrolyte near the anode mesh plates 90, 98a, which leads to an increased pressure with respect to the water / electrolyte pressure on the other side of the membrane 116. This pressure difference is sufficient to ensure that would cause gaseous oxygen to move through the membrane, so that mixed oxygen and hydrogen are released through the gas outlet pipe 133 and column 144. Since there is no return path for water / electrolyte pump 138, the pressure near the mesh plates 90, 98a will increase further to a value at which the difference is sufficient to keep the water / electrolyte also can pass through the membrane 116. Typically required within 1.5-10 lb / in ² pressure difference to allow the passage of gas, and the pressure difference within 1 0-40 lb / in ² for water / electrolyte.

 Although only three cellular devices 125 are depicted, it is clear that any number of them connected in series can be formed.

 FIG. 17 depicts another embodiment of a stop valve and gas purification device 160 for cleaning the released gas (s) before subsequent use. The device 160 is usually filled with water to a level that is half of the total height of the device. The level is controlled by a float switch 162. Water is supplied through the inlet 164. A transparent tube 166 is also built in, which serves to visually indicate the water level.

 Gaseous hydrogen and / or oxygen from the gas receiver under pressure enter the inlet pipe 168, which has an outlet 170 below. Gases pass down the pipe 168 and exit the hole 170, in the form of bubbles rise upward into the inner column 172, which is also filled with water supplied, thus performing an initial purification to remove sodium hydroxide. Then, gas enters the downwardly directed pipe 174 and exits its open end, again passing through water to the outer chamber 176 to be further cleaned, and thus is pressurized in a volume above the water level for subsequent exit from the outlet 176.

 Mixed gaseous hydrogen and oxygen leaving the outlet 178, say, to a welding tip (not shown) are in the correct stoichiometric proportions as a result of the electrolytic process, and you can be sure that a neutral flame is generated during combustion. The products of the combustion process are only heat and water vapor.

 If the gases are produced separately, scrubbers 160 are used with two stop valves; the gases must then be mixed in the mixing chamber, which will also produce the mixture in the correct stoichiometric proportion.

 If there is an explosion that "returns" through the outlet 178 from the welding tip, then it must be extinguished by water inside the device 160, and the explosion energy is absorbed by the displacement of water in both the outer chamber 176 and the inner column 172, and this offset also cuts off the flow of incoming gas into the pipe 168. In this case, there should be no possibility of the explosion spreading towards the bank of electrolytic cells producing gases. Water in the device 160 thus acts as a gas purifier and stop valve.

 FIG. 18 shows a welding tip 180 in cross section. Gaseous hydrogen and oxygen come from the inlet tube 182, are passed through a needle valve 184, and thus enter the expansion chamber 186. The expansion chamber 186 comprises a backfire extinguishing control device, which consists of a cylindrical backfire damper 188, typically made of 5 μm stainless steel mesh. During normal operation, gases flow through a backfire extinguisher 188 and thus to an outlet or nozzle 190, where gas is burned or ionized during plasma formation.

 In the event that a backfire occurs, the backfire suppressor 188 does not allow further propagation in the reverse direction of the flame, which physically cannot pass through openings as small as, say, 5 microns. Associated with this is the effect of heat absorption by the material from which the damper 188 is made, which leads to the dissipation of the flame energy, and which, therefore, contributes to the destruction of the flame.

The use of hydrogen and / or oxygen in welding and cutting using electrolysis allows to reach temperatures of the order of 6000 ^o C with the ability to produce gas in the required quantity. No gas stored in the cylinder. It is also possible to weld with a high-quality flame with high-purity gas, and it is also possible to melt ceramic materials.

All of the following materials can be welded: carbon steel, cast iron, stainless steel, aluminum, brass, silver solder, copper and ceramic. The following iron-containing and iron-containing materials, due to the possibility of producing pure hydrogen passing through a direct current arc generating a hydrogen plasma stream (H ₂ ---> H ₁ ), can be easily cut: carbon steel, cast iron, stainless steel, aluminum, brass and copper.

 An embodiment of the invention can provide a continuous supply of hydrogen gas at a high flow rate. If so, then the invention is well suited for those applications that consume a large amount of hydrogen. An example of such a process is the Plascon (TM) waste decomposition process developed by Australian CSIBO's Division of Manufacturing Technology. A review of the Plascon process can be found in CS1BO Journal "Ecos, Volume 68, Winter 1991".

 One use of gaseous hydrogen and oxygen produced by the apparatus described above is the thermal decomposition of waste without burning atmospheric oxygen. This procedure requires the supply of gaseous hydrogen and oxygen on demand. The electrolysis apparatus described above can, with increasing size, produce the necessary gas flow in order to burn gaseous waste on a commercial scale.

FIG. 19a and 19b depict the configuration of a furnace used to decompose said gaseous pollutant emissions. FIG. 19a shows a cross section of the furnace 200. A cross section along the midline is shown in FIG. 19b. The furnace 200 has a hemispherical combustion chamber 202. Emissions, which may contain a mixture of fumes containing bicarbonates and other volatile pollutants as a product of industrial waste, are injected into the combustion chamber through inlet 206. There are two sources of mixing gaseous hydrogen and oxygen in a 2: 1 stoichiometric ratio, which are in the upper and lower quadrants of the combustion chamber 202. These gases are supplied by two gas inlets 208 located at points located on diametrically opposite sides of the furnace 200. See all of the hydrogen and oxygen and emissions generated inside the combustion chamber is ignited by a spark from a spark plug 210 or the like and burns out at a temperature of at least 4000 ^o C, thus providing energy for the dissociation of molecules of all contaminants into harmless components that can be released in atmosphere. During combustion, atmospheric oxygen does not burn. The "focusing" of the combustion chamber 202, which also improves the mixing of gas flows, contributes to the completion of the combustion of contaminants.

 Thermocouple 212 measures the temperature inside the silicone fiber refractory heat insulating material 214 surrounding the combustion chamber 202. The liner 216 used in the furnace 200 is typically made of stainless steel.

The furnace design is made of seven (only four are shown) concentrically arranged nozzle sets 212, as is clearly shown in FIG. 19b. The nozzles 222 are directed toward a common intersection point at the epicenter 204 of the combustion chamber 202. The cooling water supplied through the inlet 218 and exiting through the outlet 220 is designed to maintain the temperature of the nozzles 222 below 300 ^° C. Over 300 ^° C, hydrogen gas tends to " reverse combustion. "

The path of the flow of hydrogen gas and oxygen to the nozzles 222 from the inlet openings 208 has four (minimum) direction changes of 90 ^° C. This is intended to reduce the linear inertia of the hydroxy flame in the event of reverse combustion and, thus, cause the flame to extinguish itself . This is particularly advantageous when hydrogen burns at a speed of 3600 m / s.

 FIG. 20 depicts, in a block diagram, a multi-module cutting and welding device 230. Direct current energy is supplied to the device from an AC / DC converter 232. A commercially available AC voltage source is provided for connection to a device 234 welding an alternating voltage electric arc, while a converted DC output voltage is intended to be connected to a device welding an alternating voltage electric arc or a cutting device 236. Voltage supplied from the source output DC voltage is supplied to the electrolytic cellular device 238 to obtain in this case separated hydrogen gas and ki loroda. Gaseous hydrogen and oxygen are supplied to the gas welding device 240. Hydrogen (and oxygen for secondary injection) is available for connection to a plasma cutting device 242. Hydrogen passes through a direct current arc to produce a plasma stream, and during secondary injection, oxygen is introduced into the plasma stream to obtain the effect of oxidizing plasma cutting, which increases the cutting efficiency. Using this process, you can cut the thickness of the material up to 150 mm. It should be noted that the introduction of oxygen in a downward flow from tungsten electrodes destroys any oxidation of the electrodes.

 For the MIG / TIG 244 device, one hydrogen gas is produced in plasma form, in contrast to the usually inert gas. A plasma source also requires an alternating or direct current source.

 Converter 232 may be of any conventional design, typically having a multi-pin transformer to select a suitable rectified voltage. The electrolytic device 238 may be any of the previously described embodiments and comprise a scrubber and a stop valve. The various cutting and welding devices described 234, 236, 240, 242, 244 are also common.

 The multimodule device 230 thus provides greater flexibility for the user to be able to select with a single device the particular desired cutting or welding mode. It is clear that a device comprising any one or a combination of welding / cutting devices is provided by the present invention.

 FIG. 21 depicts a multi-module device 230 with a high degree of detail. As described above, the electrolytic generator 238 individually produces gaseous hydrogen and oxygen and can also produce gaseous hydrogen and oxygen as a mixture.

 The power supply device 232 includes a multi-output transformer 246. The reduced voltage is rectified by a bridge rectifier 247. The output rectified voltage is then connected by terminals 248 to a block of cells 238 containing 30 cells through a contactor 249, which is driven by a pressure switch 250. The switch 250 is in turn driven activated by a pressure sensor 251, which senses the gas pressure level inside the cell block 238. Thus, the contactor 249 is controllable to remove the voltage supply to the unit to cells 238 when establishing the working pressure. Contactor 249 operates on demand using gas.

 Thus, gas is produced in the right quantities, and usually 15 liters at any given time. These 15 l of gases contain 10 l of hydrogen and 5 l of oxygen.

 Gases come from the gas cleaning columns 156, 158 of the cell block 238. Since the cyclic system is closed, the pressure in each column will be compensated by the pressure in the other, thereby maintaining a constant desired level of gas production. If, however, the water level is too high due to excessive use of any gas, then the corresponding float switch 254, 255 in the corresponding column 156, 158 will block the flow of gas by closing the corresponding solenoid valve 256, 257.

 The float switches 254, 255 actuate the solenoid valves 256, 257 from an AC voltage source 258 extending from the transformer 246. Other float switches located in the stop valve and scrubbers 160 and the charge pump 138 are also powered by an alternating voltage source 258.

 Two flow controllers 261, 262 are combined to maintain the desired back pressure in the columns 156, 158, so that the system is always under pressure, even if the system is turned off and / or the gases were exhausted through the gas outlets, gas outlets 263, 264 stop valves / gas cleaning devices 160 or welding tip 265.

 Another way to get the mixture is when hydrogen gas and oxygen, in contrast to the separation of gases in the block of cells 238, passed through a stop valve and purification devices 160, then the selection valve 266 allows the gases to mix and enter the welding tip, where they are ignited and burned, to be used for hydrogen / oxygen welding.

 If gaseous hydrogen and oxygen are supplied separately and are required for the hydrogen plasma cutting device 242 and / or the hydrogen plasma MIG / TIG welding device 244, then the select valve 266 prevents the two gases from mixing.

 The voltage supply device 232 is a conventional device with a multi-output transformer 246, comprising a reactive winding 267 and a range select switch 268 that allows selection of the output voltage level. The generated secondary alternating voltage can also be rectified by a rectifier 247 to obtain a constant output voltage. All of these output voltages are then supplied to a polarity selector 269, allowing the user to choose between alternating or constant output voltage and select the appropriate polarity for the output constant voltage.

 The output 248 of the power source 232 is shown connected to the block of electrolytic cells 238, however, the power source can also be connected to other types of welding or cutting equipment, such as those shown in FIG. 20.

 Next, the output 271 supplies the necessary DC energy to the welding device 244 MIG / TIG immersion in hydrogen plasma and a hydrogen plasma oxidizing cutting device 242. Next, the output 272 of the alternating current and the output 273 of the direct current provide the necessary current to obtain the arc for MTG or TIG processes.

 For a block of cells 238 and electric arc devices 234, 263, output voltages in the range of 20-60 V are required, while welding MIG / TIG devices usually operate at an output voltage of 30-60 V (alternating or constant). Plasma cutting and plasma immersion, which is carried out by the plasma device 242, usually requires a supply of 120 V DC.

Claims (12)

 1. An electrolyzer for electrolysis of water, comprising a plurality of electrodes forming the anode (52) in the form of a stack, each electrode-anode consisting of a flat plate, a plurality of electrodes forming the cathode (54) in the form of a stack, each electrode-cathode consisting of a flat plate, and the electrode anodes and electrode cathodes alternate, characterized in that it has at least one conductive first connecting element (56) passing through the alternating electrodes (52, 54) and providing electrical connection only with each electrode-anode (52), and at least one conductive second connecting element (58) passing through alternating electrodes (52, 54) and providing electrical connection only with each cathode electrode (54).  2. The electrolyzer according to claim 1, characterized in that the group in the form of a stack of electrodes-anodes (52) forms an anode cellular block and the group in the form of a stack of electrodes-cathodes (54) forms a cathode cellular block, whereby each anode cellular block only part of its length is blocked by the corresponding cathode cell block.  3. The electrolyzer according to claim 2, characterized in that in each mesh block, the corresponding first and second connecting elements (56, 58) extend only to the length of the corresponding mesh block.  4. The electrolyzer according to claim 1, characterized in that each electrode has a hexagonal shape and the first connecting elements (56) pass through the electrode at a point close to each alternating vertex, and the second connecting elements (58) pass through the electrode next to other alternating tops.  5. The electrolyzer according to any one of claims 1 to 3, characterized in that each electrode (90) has a perforated inner part (92) and an outer edge part (94) with holes (100, 102) through which the first and second connecting elements.  6. The electrolyzer according to claim 5, characterized in that the electrodes (90) have a circular shape.  7. A battery of elements for electrolysis of water, which contains a plurality of electrically connected in series electrolytic cells according to any one of the preceding paragraphs and one or more of the series-connected electrolytic cells have a series electrical connection and are physically mounted in parallel.  8. The battery of cells according to claim 7, characterized in that it has the same number of electrolyzers in each series connection, the parallel physical installation is formed by a tightly packed array of series-connected electrolyzers and further comprises at least one connecting bridge (74, 76) at each end of each the electrolyzer, and the bridges (74, 76) at each end respectively connect the anode electrodes (52) of each electrolyzer and the cathode electrodes (54) of each electrolyzer form a series of electrical some connection.  9. An electrolysis system comprising an electrolyzer or a battery of cells according to any one of the preceding paragraphs, a reservoir (72) adapted to contain and immerse said electrolyzer or battery of cells (125) at least in water, a direct current power supply whose positive terminal is connected to anode electrodes (52), and the negative terminal of which is connected to the cathode electrodes (54) by means of the corresponding first and second connecting elements (56, 58) for the release of gaseous oxygen and hydrogen, respectively -retarded with said electrodes, the anodes and cathodes of said electrodes.  10. The electrolysis system according to claim 9, characterized in that it further includes pipeline means (142, 146) for collecting said gaseous oxygen and hydrogen in the form of a gas mixture and gas cleaning means (156, 158) through which the collected gas passes, gas cleaning means have at least two separate paths along which the mixed gas is forced to pass, being separated by at least one cleaning liquid.  11. The electrolysis system according to claim 10, characterized in that said gas cleaning means comprise a reservoir (140) filled with a cleaning fluid to a certain level (h) of the reservoir and at least two vertically arranged columns (142, 144) inside the reservoir, the first the column has an upper end for receiving the collected mixed gas and a lower end open to the cleaning liquid, and the second column has an upper end for receiving the pre-purified gas and a lower end open for the cleaning Fluid, wherein the second purified gas passes to the outlet (148, 150).  12. The electrolysis system according to claim 10 or 11, characterized in that it further comprises means for restricting the flow through which said collected gas passes, thereby creating a back pressure on the water in the tank. Priority on points:
09/06/1993 according to claims 1 - 4, 7 - 9;
08/02/1994 according to claims 5 and 6;
04/19/1994 according to claims 10-12.

Images