FIELD OF THE INVENTION
The present invention generally relates to an electrolysis apparatus and more particularly to a low voltage electrolysis apparatus for the efficient electrical decomposition of water.
BACKGROUND OF THE INVENTION
Electrolysis of water is the electrical decomposition of water into diatomic hydrogen and oxygen gases. Devices for the electrolysis of water generally comprise a series of electrodes submerged in an electrolytic solution whereby an electrical current is applied, resulting in the production of hydrogen and oxygen gases.
The efficiency of a device for the electrolysis of water is measured by the electrical conversion ratio of produced hydrogen and oxygen gas compared to the amount of electrical energy put into the device. Prior attempts to create hydrogen and oxygen by the electrolysis of water generated not only oxygen and hydrogen gas but also a large amount of thermal energy and water vapor, which lowers the efficiency of the overall system and contaminates the oxygen and hydrogen gas with unnecessary water vapor.
Two of the most commonly mentioned names in the history of Oxy-Hydrogen generator production are Brown (U.S. Pat. No. 4,014,777) and Stowe (U.S. Pat. No. 5,231,954). The BROWN and STOWE generators are extremely different, and they both have poor efficiency due to excessive thermal heating of the electrolyte solution.
The STOWE system is a single-cell system that is rather identical to all the single-cell systems built prior to and after the patenting of the STOWE system. It is quite inefficient because it releases a significant amount of heat, and it requires a substantial amount of energy to function. Also, the cables used to connect a power supply to the generator must be specifically pre-dimensioned to suit the system in order to avoid melting. Many “copies” of that system are in circulation today and are used as boosters to improve the combustion process within internal combustion engines used in vehicles. That type of electrolysis device generally uses the vehicle's alternator as a source of power, and it requires approximately 5 Wh of energy in order to produce one liter of gas. Producing larger quantities of gas by using this system does not make economical sense as significant amounts of energy are wasted.
The BROWN electrolysis device is designed as a multi-cell series with 2 Volts in between every plate. The electrolysis device requires 8 kWh of energy to produce 2000 L of gas (4 Wh for 1 L). It is more efficient than most of the other multi-cell systems, as the designer isolated the plates (anodes and cathodes) by using frame-shaped spacers with small holes on the top and the bottom. The holes on the top are used for exhausting the oxygen and hydrogen gases while holes on the bottom are used for refilling the electrolyte level. Due to the fact that the cells use the same electrolyte that passes through the holes, it causes current leaking between the pairs of cathode and anode plates resulting in decreased efficiency.
Therefore, there is a need for a device that produces oxygen and hydrogen with improved efficiency, i.e., a device that generates more hydrogen and oxygen and less heat.
SUMMARY OF THE INVENTION
Embodiments of the present device for the electrolysis of water provide considerable oxygen and hydrogen gas production and reduced thermal waste. This device for the electrochemical decomposition of water is comprised of a number of electrodes for applying electricity to an electrolyte solution to break down the water into its elements of hydrogen and oxygen. The components of a device for the electrochemical decomposition of water include electrodes submerged in water and an electrical current that is applied to the electrodes.
The present device comprises a number of modular cells, arranged in a side-by-side array, that are electrically isolated from each other. This is done by isolating the aqueous electrolyte solution of each cell and by not allowing any of the electrolyte solution to interact with the other electrolyte solutions in other cells. As oxygen and hydrogen are generated, water is consumed, creating a need to refill each cell with additional water. This act may be accomplished via a refill port located on the electrode housing cell. During the production of hydrogen and oxygen, the gas is collected through an exhaust port and delivered to a point of use or collection device. Generally the electrodes are a pair of square plates, submerged in water, and aligned vertically so as to allow the gas to rise naturally by buoyant forces.
The device for the electrolysis of water is designed as a modular system, meaning that each cell has its own separate housing. This concept allows one to build different gas-producing capacity electrolysis devices, with a number of combinations between cells, different area sizes of electrodes, and different ways of connecting the cells (series, parallel, series-parallel). Some of the many advantages of this particular system are easy maintenance and even easier repairs, as it is much easier to replace a potentially faulty cell then repair the entire electrolysis device as a whole, due to the fact that large-scale production of cells would be relatively inexpensive. The system is very compact and adaptive to its environments. The system can be made custom, according to the needs of the buyer, based on size, shape, and gas production required. Further, by isolating the electrolyte solution between modular cells, a higher conversion ratio of the gas production compared to energy input is achieved.
By using lower voltage, approximately 2 volts, conversion is more efficient. In my device, it is very important to follow the rule of having about 2 V between each pair of cells, which means that, if using a source with 12-14 V, it is ideal to design an electrolysis system with 6-8 cells. For large and higher voltage applications (for various industrial thermal processes such as those found in the glass industry, refineries, large heaters, or even metal-melting stoves), larger voltages of hundreds or even several thousands of Volts may be used. These large voltage sources use AC Voltage, although it is a rather simple conversion to DC Voltage through industrial size rectifiers and current regulators. Also, production of gas can be regulated through regulations of voltage on the AC source. A combination of the two forms of regulators creates a simple and highly efficient system.
The current density of the electricity flowing through the system is also important. The current density is measured by the current per unit area, or J=I/A, where I is the electrical current in amperes and A is the area through which the current is flowing. The current must be sufficiently low to keep the conductor from melting or burning up and to maintain the insulative properties of the insulation material.
Increasing the size of the plate while maintaining the amperage flowing through the electrodes decreases the current density. Decreasing the current density decreases the amount of energy lost due to heating of the system, thereby increasing the overall efficiency of the system. Current densities between 0.3 Amp/square inch and 0.12 Amp/square inch increase the efficiency of the system without excessively wasting construction material.
This system is also very useful for small and large scales of oxygen and hydrogen production. In order to acquire the two gases separately, separators (ion exchange membrane-cation exchange membrane) or various forms of diaphragms can be used between the cells. It is crucial that the separators are chemically resistant to the electrolyte used in the process, as oxidations of the separators would cause plugging of their pores and hence faulting of the separation process.
One embodiment of the device contains a refill assembly comprised of at least a sensor, a refill reservoir holding reserve fluid, and a valve controller that opens when the level of the water solution is below a certain level. Different refill devices may be incorporated into the design of the electrolysis device. In one embodiment of such a device, there is a level sensor that detects a level of the fluid in the device, and, when the level of fluid in the device reaches a predetermined level, a pump or gravity feed assists the device by adding fluid. The valve controller may be mechanical, such as a float valve or other mechanical sensor, or an electrical sensor that controls an electrically-actuated valve or engages a pump. Another implementation of a refill assembly is simply a timed refill assembly, where the interval between refills is based on a duration of time or an amount of gas that is generated from the device.
In one embodiment, the electrodes are spaced very close to each other to reduce resistance due to the fluid between the electrodes. Decreasing the distance between electrode plates increases the production of hydrogen and oxygen by increasing the flow of electrical current between the electrode plates. However, if the electrodes are spaced too closely, oxygen and hydrogen gases formed on the surface of the plates may coalesce into large, highly electrically-resistant bubbles, thereby reducing current flow. Therefore, a minimum distance should be maintained to reduce this phenomenon.
Generally, pure water is not preferred as the electrolysis medium due to the relatively high electrical resistance of pure water. The use of an electrolyte increases the conductivity of the aqueous medium. In one embodiment, sodium hydroxide, an electrolyte that creates an excess of hydroxyl ions when dissolved, is added to water to create a basic solution. If this aqueous solution is permitted to interface with the atmosphere, atmospheric carbon dioxide will form carbonic acid in the aqueous solution, which will further react with hydroxyl ions, reducing the preferred electrical properties of the solution. In one embodiment of the present device, a mechanism for isolating the aqueous solution from atmospheric carbon dioxide is incorporated into the design. One such embodiment includes the use of a gasket attached to a removable lid. When the lid is attached to the modular electrolysis cell, the gasket prevents atmospheric carbon dioxide from entering. Another embodiment includes the use of a lid on the device that is chemically sealed.
Hydrogen and oxygen gases are highly explosive; as a result, a device that combines electricity with hydrogen and oxygen runs the risk of exploding. Therefore, it is important to incorporate some sort of a safety device into the present electrolysis device. In some embodiments, the safety device comprises a wet flashback arrester that reduces the magnitude of a possible explosion by forcing all of the gas emitted by the individual electrode housing cells through an incombustible liquid medium before combining. A wet flashback arrester comprises a reservoir containing an incombustible fluid. The hydrogen and oxygen are dispersed into the liquid, below the surface of the incombustible fluid, and then collected above the surface before going to a point of use. This limits the amount of gas capable of being ignited at any time and further limits the amount of explosive energy available at one time. Additionally, dry flashback arresters may be incorporated into the design in order to reduce the flow of combustion in the gas line.
The combination of liquid reservoir, modular electrolysis cell, refill mechanism, and safety mechanisms may additionally be included in a single housing unit, making it easier to transport, store, and apply all of the parts in a variety of applications. This housing unit may serve as an additional safety device by providing protection for the hydrolysis parts as well as dampening in the event of an explosion.
The purpose of the foregoing summary is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The summary is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
Still other features and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial view of components of a device for the electrolysis of water.
FIG. 2 is a partial view of components for a modular electrolysis cell.
FIG. 3 is a schematic view of an electrolysis unit showing added safety features.
FIG. 4 is an exploded view of a modular electrolysis cell.
FIG. 5 is a cut-away view of a modular electrolysis cell.
FIG. 6 is a depiction of a modular electrolysis cells arranged in series.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.
As shown in the figures for the purpose of illustration, the current device is embodied in a novel device for the electrolysis of water that provides high efficiency by electrically isolating the electrolyte solution.
In the following description and in the figures, likes elements are identified with like reference numerals. The use of “or” indicates non-exclusive alternatives without limitation unless otherwise noted. The use of “including” means “including but not limited to,” unless otherwise noted.
An embodiment of a device for the electrolysis of water 10 is shown in FIG. 1. The device for the electrolysis of water may be constructed from a variety of materials including high-density polyethylene, polypropylene, or other electrolyte-resistant materials. The main housing unit 30 surrounds the modular electrolysis cells, keeps the cells arranged in a formation, and provides additional functionality by making all components easy to transport and integrate into a variety of different uses.
An embodiment of a device for the electrolysis of water 10 is shown in FIG. 1. The device for the electrolysis of water may be constructed from a variety of materials including, high density polyethylene, polypropylene, or other electrolyte resistant materials. The main housing unit 30 surrounds the modular electrolysis cells, keeping the cells arranged in a formation and provides additional functionality by making all components easy to transport and integrate into a variety of different uses.
The modular electrolysis cells 12 consist of an electrolyte corrosion resistant material. The cells are made to assemble together in a side by side array. Internally each electrolysis cell contains a cathode plate 22 and an anode plate 20 attached to the corresponding anode terminals 16 and cathode terminals 14, between the two plates there is an insolating electrode spacer 50. In order to isolate the electrolyte solution from the atmosphere, the electrolysis cell 12 may use an atmospheric sealing mechanism 42.
The modular electrolysis cells would have safety devices, and the refill mechanism may all be contained in a main housing unit 30. This main housing unit 30 may provide additional safety precautions to contain any explosive forces.
FIG. 2 is a single modular electrolysis cell. Generally each modular electrolysis cell 12 is comprised of an anode plate 20 and a cathode plate 22. The cathode 22 and anode 20 plates are submerged in an electrolyte fluid 44 whereby applying electrical energy to cathode terminal 14 and anode terminal 16 leads to the generation of oxygen and hydrogen gases. The generated oxygen and hydrogen gas is collectively removed from collection port 18 where it is transported by collection line 38 to a point of use. As the water in the electrolyte solution 44 is consumed by the electrical decomposition, additional water is inserted into the collection of modular electrolysis cell 12 through the refill port 28. A level sensor 40 located in the collection modular electrolysis cell 12, senses the level of fluid in the electrolysis cell and activates the refill mechanism 62. By electrically isolating each collection modular electrolysis cell's 12 electrolyte solution 44, inefficiencies due to thermal energy generation are minimized.
FIG. 3 is a diagram showing possible additional safety features. In order to increase the safety of the system the collected hydrogen and oxygen gas collected in collection lines 38 may be isolated by an isolation mechanism 64 such as a wet flash back arrester 46 or a dry flash back arrester 48 from each modular electrolysis cell 12. Water vapor entrained in said gaseous emission may be removed by the use of a water condenser or water coalescor 52. The pressure of the system may be monitored by a pressure sensor 54 and regulated by a pressure and flow regulator 58.
FIG. 4 shows an exploded view of one of the modular electrolysis cells 12. The cell housing 24 surrounds the anode plate 20 and cathode plate 22. The cells are made to assemble together in a side-by-side array. The cell housing 12 is generally made from an electrolyte-corrosion-resistant material. Atmospheric isolating lid 20 interfaces with gasket 42 and modular cell housing 24 to form an airtight seal and isolate the electrolyte from air corrosion. Retaining bolts 74 keep anode plate 20 and cathode plate 22 in a spaced apart relationship. Electricity is applied to anode terminal 16 and cathode terminal 14. In some embodiments of the current device, level sensor 44 detects the level of fluid within modular electrolysis cell 12 and refills the cell through refill port 28. Hydrogen and oxygen gas that is generated is removed through collection port 18.
FIG. 5 shows a cross section of a modular electrolysis cell 12. Modular electrolysis cell 24 contains electrolyte solution 44. Cathode plate 22 and anode plate 20 are submerged in electrolyte solution 44. Retaining bolt 74 keeps both plates together, while insulating spacer 72 keeps the plates in a spaced apart relation. Electricity is applied to cathode terminal 14 and anode terminal 16. Hydrogen and oxygen gas created by the electrochemical decomposition of water is removed through collection port 18.
Each modular electrolysis cell 12 comprises an electrolyte-corrosion-resistant material. The cells are made to assemble together in a side-by-side array. FIGS. 4 and 5 show the internal components of each modular electrolysis cell. Internally, each electrolysis cell contains a cathode plate 22 and an anode plate 20 attached to the corresponding anode terminals 16 and cathode terminals 14. Between the two plates is an insolating electrode spacer 72. In order to isolate the electrolyte solution from the atmosphere, the electrolysis cell 12 may use an atmospheric sealing mechanism 42.
The modular electrolysis cells would have safety devices, and the refill mechanism may all be contained in a main housing unit 30. The main housing unit 30 may provide additional safety precautions to contain any explosive forces.
FIG. 2 depicts the external components of a single modular electrolysis cell. Each modular electrolysis cell 12 has an anode terminal 16 and a cathode terminal 14. Applying electricity to anode terminal 16 and cathode terminal 14 generates hydrogen and oxygen. The generated oxygen and hydrogen is removed from the modular electrolysis cell 12 through collection port 18.
FIG. 3 is a schematic diagram showing possible additional safety features. As shown in FIG. 3, the main housing unit may further comprise a wet flashback arrester 46 or dry flashback arrester 48 to prevent explosions from reaching and damaging the modular electrolysis unit. Additionally, a water condenser 52 removes water from the hydrogen and oxygen gas line thereby removing evaporated water from the gas line. The pressure of the entire system may be monitored by a pressure sensor 54 and a pressure gauge 66 and regulated by a pressure and flow regulator 58. The safety valve 56 may further be incorporated in order to ensure the system does not create too much pressure.
FIG. 6 shows the modular electrolysis cells 12 arranged in series by connected cathode terminal 14 of each cell to the anode terminal 20 by wire 76. All of the modular electrolysis cells are contained in main housing 30, which is held together by retaining bolt 78 and retaining nut 80.
While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto, but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims.