Patent Application
20120102953
The present invention relates generally to electric power generating systems.
Power generating systems in general, and steam power plants in particular, are well known in the art. This type of power generating system uses any of a variety of heat sources to heat water in order to produce steam. The steam flows into one or more turbines which spin a generator in order to produce electricity. Common heat sources used to heat the water within the boiler are coal, lignite (brown coal), fuel oil, natural gas, oil shale and nuclear reactors. In general, these systems are scalable although the extent of scalability is driven in large part by the fuel. For example, it is easier to scale a coal-fired boiler than it is to scale a boiler utilizing nuclear energy. As the temperature, pressure and quantity of steam is varied, other aspects of the system are typically scaled as well. For example, the need for pre-heaters and super-heaters depends, in part, on the size of the system. Additionally, turbine complexity varies with power plant size, ranging from small power generation systems utilizing only a single turbine to large power generation systems utilizing a series of interconnected turbines that include high pressure, intermediate pressure and low pressure turbines.
Although steam-electric power plants are well known, the current systems exhibit one or more problems. First, as previously noted, the extent of scalability varies, thus making certain power plants unusable or overly inefficient for certain applications (e.g., using a nuclear steam-electric power plant to provide power to a small community). Second, all current steam-electric power plants generate considerable environmental waste. For example, all fossil fuel based systems generate carbon dioxide, a major contributor to global warming. Fission-based nuclear reactors, while not generating carbon dioxide, produce large quantities of radioactive waste, typically on the order of 20 to 30 tons per year, which can remain toxic for hundreds of thousands of years. In addition to the problems of radioactive waste containment, removal and storage, this form of waste also adds a high degree of risk to the operation of such a power plant, both to local residents and those living hundreds of miles away. For example, the accident that occurred at Chernobyl in the Ukraine increased the radiation levels in Scotland to over 10,000 times the norm. Additionally, some nuclear reactor waste can be used to produce nuclear weapons (i.e., bombs), thus adding the cost of security to the operating costs of the power plant.
In addition to the environmental and safety issues associated with current steam-electric power plants, these systems can also lead to increased vulnerability to potential supply disruption, whether the supply is a fossil fuel such as coal or a nuclear fuel such as uranium. Additionally, obtaining such fuels, for example by mining, can have significant adverse effects on the ecosystem in the area in which the fuel is mined and processed.
Accordingly, what is needed is a steam-electric power plant that is scalable and environmentally friendly. The present invention provides such a system.
The present invention provides a power generating system and a method of operating the same, the system utilizing an electrolytic heating subsystem. The electrolytic heating subsystem is a pulsed electrolysis system that, during operation, heats the medium contained within the electrolysis tank. The medium is pumped out of the electrolysis tank and through a conduit that is coupled to at least one heat exchanger. A second conduit, containing a working fluid, circulates the working fluid through the heat exchanger, thereby heating the working fluid to a temperature above its boiling point, causing at least a portion of the working fluid to be converted to vapor (e.g., steam). The vapor is circulated through a steam turbine, causing its rotation and, in turn, an electric generator coupled to the steam turbine.
In one embodiment of the invention, the power generating system includes an electrolytic heating subsystem comprised of an electrolysis tank, a membrane separating the electrolysis tank into two regions, at least one pair of low voltage electrodes, at least one pair of high voltage electrodes, a low voltage source, a high voltage source, and means for simultaneously pulsing both the low voltage source and the high voltage source. The system is further comprised of a first conduit coupling the electrolysis tank to a heat exchanger and a second conduit coupling the heat exchanger to a steam turbine, the steam turbine being coupled to a generator. Circulating within the first conduit is the electrolysis medium. Circulating within the second conduit is a working fluid which, upon heating, becomes vapor (e.g., steam). The system can also include a condenser for condensing the vapor after it passes through the steam turbine. The system can also include circulation pumps. The heat exchanger can be comprised of a single heat exchanger or a multi-stage heat exchanger. The system can also include one or more of a variety of sensors (e.g., electrolysis medium temperature monitor(s), working fluid temperature monitor(s), electrolysis medium level sensors, electrolysis medium pH sensors, electrolysis medium resistivity sensors, etc.). The system can also include a system controller that can be coupled to the electrolytic heating subsystem (e.g., the low and/or high voltage sources, the pulsing means, etc.), and/or a circulation pump(s), and/or the system sensors. The system can further be comprised of at least one electromagnetic coil capable of generating a magnetic field within a portion of the electrolysis tank. The system can further be comprised of at least one permanent magnet capable of generating a magnetic field within a portion of the electrolysis tank.
In one embodiment of the invention, the power generating system includes an electrolytic heating subsystem comprised of an electrolysis tank, a membrane separating the electrolysis tank into two regions, at least one pair of high voltage electrodes, a plurality of metal members contained within the electrolysis tank and interposed between the high voltage electrodes and the membrane, a high voltage source, and means for pulsing the high voltage source. The system is further comprised of a first conduit coupling the electrolysis tank to a heat exchanger and a second conduit coupling the heat exchanger to a steam turbine, the steam turbine being coupled to a generator. Circulating within the first conduit is the electrolysis medium. Circulating within the second conduit is a working fluid which, upon heating, becomes vapor (e.g., steam). The system can also include a condenser for condensing the vapor after it passes through the steam turbine. The system can also include circulation pumps. The heat exchanger can be comprised of a single heat exchanger or a multi-stage heat exchanger. The system can also include one or more of a variety of sensors (e.g., electrolysis medium temperature monitor(s), working fluid temperature monitor(s), electrolysis medium level sensors, electrolysis medium pH sensors, electrolysis medium resistivity sensors, etc.). The system can also include a system controller that can be coupled to the electrolytic heating subsystem (e.g., the voltage source, the pulsing means, etc.), and/or a circulation pump(s), and/or the system sensors. The system can further be comprised of at least one electromagnetic coil capable of generating a magnetic field within a portion of the electrolysis tank. The system can further be comprised of at least one permanent magnet capable of generating a magnetic field within a portion of the electrolysis tank.
In another aspect of the invention, a method of generating electricity is provided, the method comprising the steps of heating a liquid contained within the electrolysis tank of an electrolytic heating subsystem by performing electrolysis within the electrolysis tank, circulating the heated liquid from the electrolysis tank through a heat exchanger via a first conduit, circulating a working fluid through a second conduit coupled to the heat exchanger, wherein the working fluid is heated to a temperature above its boiling point as it passes through the heat exchanger, circulating the generated vapor through a steam turbine thereby causing the rotation of the steam turbine, and rotating a drive shaft of a generator coupled to the steam turbine thereby causing the generator to generate electricity. In at least one embodiment, the method further comprises the step of passing the vapor through a condenser after it has passed through the steam turbine. In at least one embodiment, the method further comprises the steps of circulating the heated liquid through a first heat exchanger stage and then through a second heat exchanger stage, and circulating the working fluid first through the second heat exchanger stage and then through the first heat exchanger stage. In at least one embodiment, the method further comprises the steps of circulating the heated liquid first through a first heat exchanger stage, second through a second heat exchanger stage, and then through a third heat exchanger stage, and circulating the working fluid first through the third heat exchanger stage, second through the second heat exchanger stage, and then through the first heat exchanger stage. In at least one embodiment, the method further comprises the steps of periodically measuring the temperature of the electrolytic heating subsystem, comparing the measured temperature with a preset temperature or temperature range, and modifying at least one process parameter of the electrolytic heating subsystem if the measured temperature is outside (lower or higher) of the preset temperature or temperature range. In at least one embodiment, the method further comprises the steps of periodically measuring the temperature of the working fluid, comparing the measured temperature with a preset temperature or temperature range, and modifying at least one process parameter of the electrolytic heating subsystem if the measured temperature is outside (lower or higher) of the preset temperature or temperature range. In at least one embodiment, the method further comprises the steps of periodically measuring the temperature of the liquid, comparing the measured temperature with a preset temperature or temperature range, and modifying at least one process parameter of the electrolytic heating subsystem if the measured temperature is outside (lower or higher) of the preset temperature or temperature range. In at least one embodiment, the step of performing electrolysis further comprises the steps of applying a low voltage to at least one pair of low voltage electrodes contained within the electrolysis tank of the electrolytic heating subsystem and applying a high voltage to at least one pair of high voltage electrodes contained within the electrolysis tank, wherein the low voltage and the high voltage are simultaneously pulsed. In at least one embodiment, the step of performing electrolysis further comprises the steps of applying a high voltage to at least one pair of high voltage electrodes contained within the electrolysis tank, the high voltage applying step further comprising the step of pulsing said high voltage, wherein at least one metal member is positioned between the high voltage anode(s) and the tank membrane and at least one other metal member is positioned between the high voltage cathode(s) and the tank membrane. In at least one embodiment, the method further comprises the step of generating a magnetic field within a portion of the electrolysis tank, wherein the magnetic field affects a heating rate corresponding to the electrolytic heating subsystem.
A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and the drawings.
During operation, electrolytic heating subsystem 103 becomes very hot, the temperature dependent on the operating conditions of subsystem 103 (e.g., on/off cycling time, electrode size, input power, input frequency and pulse duration, etc.). Typically subsystem 103, and more specifically medium 107 within subsystem 103, is maintained during operation at a relatively high temperature, typically on the order of at least 150°-250° C., more preferably on the order of 250°-350° C., and still more preferably on the order of 350°-500° C. It some embodiments, the system is maintained at even higher temperatures.
During operation, the heated electrolysis medium is circulated through heat exchanger 105 via first circulation conduit 109, conduit 109 coupling the heat exchanger to electrolysis tank 111. It will be appreciated that tank 111 and conduit 109 are preferably designed to operate at high pressures, thus allowing the desired temperatures to be reached while maintaining fluid 107 in a fluid state. In the illustrated embodiment the heated working fluid is pumped through circulation conduit 109 and heat exchange subsystem 105 using a circulation pump 113. Pump 113 can be a single speed or a multi-speed pump and, in at least one embodiment, is used in conjunction with a control valve 115. Control valve 115 can be a variable flow valve or other type of valve. Pump 113, alone or in combination with valve 115, controls the flow of working fluid through conduit 109, and thus to an extent the temperature achieved in the heat exchanger.
Electric power generation subsystem 101 is coupled to heat exchange subsystem 105 by conduit 117. Within conduit 117 is a working fluid. Preferably the working fluid is water although other materials such as an organic fluid can also be used.
As the working fluid within conduit 117 passes through heat exchange subsystem 105 it is heated to a temperature above its boiling point, thereby creating vapor (e.g., steam). The vapor is circulated through a turbine 119, turbine 119 being either a single-stage or a multi-stage turbine. Although turbine 119 can be coupled to a variety of devices, thereby utilizing the rotary motion of the turbine to perform mechanical work, preferably turbine 119 is coupled to an electric generator 121, for example via direct linkage between the shaft of the turbine and the drive shaft of the generator. After the working fluid passes through turbine 119 it is cooled and condensed within a condenser 123. Preferably the working fluid is continually cycled through the steam process via circulation pump 125.
In a preferred embodiment of the invention, a system controller 127 controls the performance of the system by varying one or more operating parameters (i.e., process parameters) of electrolytic heating subsystem 103 to which it is attached via power supply 129. Varying operating parameters of power supply 129 and thus subsystem 103, for example cycling the subsystem on and off or varying other operational parameters as described further below, allows the subsystem to be operated at the desired temperature. Preferably at least one temperature monitor 131, coupled to subsystem 103, allows controller 127 to obtain feedback from the system as the operational parameters are varied. Preferably in addition to monitoring the temperature of subsystem 103, the temperature is monitored throughout system 100 thus allowing system operation to be monitored and optimized. For example, preferably the temperature of the electrolysis medium within conduit 109 is measured and monitored by system controller 127 using a pair of temperature monitors 133 and 135, both as the medium enters and as it exits heat exchange subsystem 105. Additionally, preferably the temperature of the working fluid within conduit 117 is measured and monitored by system controller 127 using a pair of temperature monitors 137 and 139, both as the working fluid enters and as it exits heat exchange subsystem 105. Additionally, in at least one preferred embodiment, the circulation pumps (e.g., pumps 113 and 125) and the control valves (e.g., flow valve 115) are also coupled to, and controlled by, controller 127. It will be appreciated that the system may also utilize other system monitors thus allowing complete system performance to be monitored and optimized. Exemplary parameters that can be monitored to provide system performance information include turbine rotation speed, steam temperature and pressure, generator output, etc.
It is often desirable to heat the working fluid in stages, this approach typically allowing improved optimization. In at least one preferred embodiment, the working fluid undergoes three heating stages; preheating, vaporization, and superheating. During the second stage, only the vapor is removed and sent on to the superheating stage during which additional heat can be added to the saturated vapor.
Multi-stage heating systems can also be used with multiple electrolytic heating subsystems as shown in the exemplary embodiment of
Particulars of the electrolytic heating subsystem will now be provided. It will be appreciated that the following configurations can be used for systems utilizing a single electrolytic heating subsystem as shown in
Tank 111 is comprised of a non-conductive material. As with conduit 109 and conduit 117, tank 111 and all fittings and couplings associated with the tank or with either conduit are designed to accommodate the operational pressures of the subsystems. The size of tank 111 is primarily selected on the basis of the desired system output, i.e., the desired temperature as well as the expected flow rate of the electrolysis medium since the flow rate determines the rate at which heat is withdrawn from the electrolytic subsystem. Although tank 111 is shown as having a rectangular shape, it will be appreciated that the invention is not so limited and that tank 111 can utilize other shapes, for example cylindrical, square, irregularly-shaped, etc. Tank 111 is substantially filled with medium 107. In at least one preferred embodiment, liquid 107 is comprised of water, or more preferably water with an electrolyte, the electrolyte being an acid electrolyte, a base electrolyte, or a combination of an acid electrolyte and a base electrolyte. Exemplary electrolytes include potassium hydroxide and sodium hydroxide. The term “water” as used herein refers to water (H2O), deuterated water (deuterium oxide or D2O), tritiated water (tritium oxide or T2O), semiheavy water (HDO), heavy oxygen water (H218O or H217O) or any other water containing an isotope of either hydrogen or oxygen, either singly or in any combination thereof (for example, a combination of H2O and D2O).
A typical electrolysis system used to decompose water into hydrogen and oxygen gases utilizes relatively high concentrations of electrolyte. Subsystem 103, however, has been found to work best with relatively low electrolyte concentrations, thereby maintaining a relatively high initial water resistivity. Preferably the water resistivity prior to the addition of an electrolyte is on the order of 1 to 28 megohms. Preferably the concentration of electrolyte is in the range of 0.05 percent to 10 percent by weight, more preferably the concentration of electrolyte is in the range of 0.05 percent to 2.0 percent by weight, and still more preferably the concentration of electrolyte is in the range of 0.1 percent to 0.5 percent by weight.
Separating tank 111 into two regions is a membrane 403. Membrane 403 permits ion/electron exchange between the two regions of tank 111. Assuming medium 107 is water, as preferred, small amounts of hydrogen and oxygen are produced during operation. Accordingly membrane 403 also keeps the oxygen and hydrogen bubbles produced during electrolysis separate, thus minimizing the risk of inadvertent recombination of the two gases. Exemplary materials for membrane 403 include, but are not limited to, polypropylene, tetrafluoroethylene, asbestos, etc. Preferably tank 111 also includes a pair of gas outlets 405 and 407, corresponding to the two regions of tank 111. The volume of gases produced by the process can either be released, through outlets 405 and 407, into the atmosphere in a controlled manner or they can be collected and used for other purposes.
As previously noted, since the electrolytic heating subsystem is designed to reach relatively high temperatures, the materials comprising tank 111, membrane 403 and other subsystem components are selected on the basis of their ability to withstand the expected temperatures and pressures. As previously noted, the subsystem is intended to operate at relatively high temperatures, typically at least 150°-250° C., more preferably on the order of 250°-350° C., and still more preferably on the order of 350°-500° C. Accordingly, it will be understood that the choice of materials for the subsystem components and the design of the subsystem (e.g., tank wall thicknesses, fittings, etc.) will vary, depending upon the intended subsystem operational parameters, primarily temperature and pressure.
Replenishment of medium 107 can be through one or more dedicated lines.
In at least one embodiment of the electrolytic heating subsystem, two types of electrodes are used, each type of electrode being comprised of one or more electrode pairs with each electrode pair including at least one cathode (i.e., a cathode coupled electrode) and at least one anode (i.e., an anode coupled electrode). All cathodes, regardless of the type, are kept in one region of tank 111 while all anodes, regardless of the type, are kept in the other tank region, the two tank regions separated by membrane 403. In the embodiment illustrated in
The first type of electrodes, electrodes 417/419, are coupled to a low voltage source 421. The second type of electrodes, electrodes 423/425, are coupled to a high voltage source 427. In the illustrations and as used herein, voltage source 421 is labeled as a ‘low’ voltage source not because of the absolute voltage produced by the source, but because the output of voltage source 421 is maintained at a lower output voltage than the output of voltage source 427. Preferably and as shown, the individual electrodes of each pair of electrodes are parallel to one another; i.e., the face of electrode 417 is parallel to the face of electrode 419 and the face of electrode 423 is parallel to the face of electrode 425. It should be appreciated, however, that such an electrode orientation is not required.
In one preferred embodiment, electrodes 417/419 and electrodes 423/425 are comprised of titanium. In another preferred embodiment, electrodes 417/419 and electrodes 423/425 are comprised of stainless steel. It should be appreciated, however, that other materials can be used and that the same material does not have to be used for both the low and high voltage electrodes. Additionally, the same material does not have to be used for both the anode(s) and the cathode(s) of the low voltage electrodes, nor does the same material have to be used for both the anode(s) and the cathode(s) of the high voltage electrodes. In addition to titanium and stainless steel, other exemplary materials that can be used for the low voltage and high voltage electrodes include, but are not limited to, copper, iron, steel, cobalt, manganese, zinc, nickel, platinum, palladium, aluminum, lithium, magnesium, boron, carbon, graphite, carbon-graphite, metal hydrides and alloys of these materials. Preferably the surface area of the faces of the low voltage electrodes (e.g., electrode 417 and electrode 419) cover a large percentage of the cross-sectional area of tank 111, typically on the order of at least 40 percent of the cross-sectional area of tank 111, and more typically between approximately 70 percent and 90 percent of the cross-sectional area of tank 111. Preferably the separation between the low voltage electrodes (e.g., electrodes 417 and 419) is between 0.1 millimeters and 15 centimeters. In at least one embodiment the separation between the low voltage electrodes is between 0.1 millimeters and 1 millimeter. In at least one other embodiment the separation between the low voltage electrodes is between 1 millimeter and 5 millimeters. In at least one other embodiment the separation between the low voltage electrodes is between 5 millimeters and 2 centimeters. In at least one other embodiment the separation between the low voltage electrodes is between 5 centimeters and 8 centimeters. In at least one other embodiment the separation between the low voltage electrodes is between 10 centimeters and 12 centimeters.
In the illustrated embodiment, electrodes 423/425 are positioned outside of the planes containing electrodes 417/419. In other words, the separation distance between electrodes 423 and 425 is greater than the separation distance between electrodes 417 and 419 and both low voltage electrodes are positioned between the planes containing the high voltage electrodes. The high voltage electrodes may be larger, smaller or the same size as the low voltage electrodes.
As previously noted, the voltage applied to the high voltage electrodes is greater than that applied to the low voltage electrodes. Preferably the ratio of the high voltage to the low voltage applied to the high voltage and low voltage electrodes, respectively, is at least 5:1, more preferably the ratio is between 5:1 and 100:1, still more preferably the ratio is between 5:1 and 33:1, and even still more preferably the ratio is between 5:1 and 20:1. Preferably the high voltage generated by source 427 is within the range of 50 volts to 50 kilovolts, more preferably within the range of 100 volts to 5 kilovolts, and still more preferably within the range of 500 volts to 2.5 kilovolts. Preferably the low voltage generated by source 421 is within the range of 3 volts to 1500 volts, more preferably within the range of 12 volts to 750 volts, still more preferably within the range of 24 volts to 500 volts, and yet still more preferably within the range of 48 volts to 250 volts. Rather than continually apply voltage to the electrodes, sources 421 and 427 are pulsed, preferably at a frequency of between 50 Hz and 1 MHz, more preferably at a frequency of between 100 Hz and 10 kHz, and still more preferably at a frequency of between 150 Hz and 7 kHz. The pulse width (i.e., pulse duration) is preferably between 0.01 and 75 percent of the time period defined by the frequency, and more preferably between 0.1 and 50 percent of the time period defined by the frequency, and still more preferably between 0.1 and 25 percent of the time period defined by the frequency. Thus, for example, for a frequency of 150 Hz, the pulse duration is preferably in the range of 0.67 microseconds to 5 milliseconds, more preferably in the range of 6.67 microseconds to 3.3 milliseconds, and still more preferably in the range of 6.67 microseconds to 1.7 milliseconds. Alternately, for example, for a frequency of 1 kHz, the pulse duration is preferably in the range of 0.1 microseconds to 0.75 milliseconds, more preferably in the range of 1 microsecond to 0.5 milliseconds, and still more preferably in the range of 1 microsecond to 0.25 milliseconds. Additionally, the voltage pulses are applied simultaneously to the high voltage and low voltage electrodes via sources 421 and 427, respectively. In other words, the voltage pulses applied to high voltage electrodes 423/425 coincide with the pulses applied to low voltage electrodes 417/419. Although voltage sources 421 and 427 can include internal means for pulsing the respective outputs from each source, preferably an external pulse generator 429 controls a pair of switches, i.e., low voltage switch 431 and high voltage switch 433 which, in turn, control the output of voltage sources 421 and 427 as shown, and as described above.
In at least one preferred embodiment, the frequency and/or pulse duration and/or low voltage and/or high voltage can be changed by system controller 127 during system operation, thus allowing the operation of the electrolytic heating subsystem to be controlled. For example, in the configuration shown in
As will be appreciated by those of skill in the art, there are numerous minor variations of the electrolytic heating subsystem described above and shown in
In an exemplary embodiment of the electrolytic heating subsystem, a cylindrical chamber measuring 125 centimeters long with an inside diameter of 44 centimeters and an outside diameter of 50 centimeters was used. The tank contained 175 liters of water, the water including a potassium hydroxide (KOH) electrolyte at a concentration of 0.1% by weight. The low voltage electrodes were 75 centimeters by 30 centimeters by 0.5 centimeters and had a separation distance of approximately 10 centimeters. The high voltage electrodes were 3 centimeters by 2.5 centimeters by 0.5 centimeters and had a separation distance of approximately 32 centimeters. Both sets of electrodes were comprised of titanium. The pulse frequency was maintained at 150 Hz and the pulse duration was initially set to 260 microseconds and gradually lowered to 180 microseconds during the course of a 4 hour run. The low voltage supply was set to 50 volts, drawing a current of between 5.5 and 7.65 amps, and the high voltage supply was set to 910 volts, drawing a current of between 2.15 and 2.48 amps. The initial temperature was 28° C. and monitored continuously with a pair of thermocouples, one in each side of the tank. After conclusion of the 4 hour run, the temperature of the tank fluid had increased to 67° C.
Illustrating the correlation between electrode size and heat production efficiency, the high voltage electrodes of the previous test were replaced with larger electrodes, the larger electrodes measuring 9.5 centimeters by 5 centimeters by 0.5 centimeters, thus providing approximately 6.3 times the surface area of the previous high voltage electrodes. The larger electrodes, still operating at a voltage of 910 volts, drew a current of between 1.73 and 1.9 amps. The low voltage supply was again set at 50 volts, in this run the low voltage electrodes drawing between 0.6 and 1.25 amps. Although the pulse frequency was still maintained at 150 Hz, the pulse duration was lowered from an initial setting of 60 microseconds to 15 microseconds. All other operating parameters were the same as in the previous test. In this test, during the course of a 5 hour run, the temperature of the tank fluid increased from 28° C. to 69° C. Given the shorter pulses and the lower current, this test with the larger high voltage electrodes exhibited a heat production efficiency approximately 8 times that exhibited in the previous test.
In a test of the exemplary embodiment of the electrolytic heating subsystem using metal members in place of low voltage electrodes, the same cylindrical chamber and electrolyte-containing water was used as in the previous test. The metal members were 75 centimeters by 30 centimeters by 0.5 centimeters and had a separation distance of approximately 10 centimeters. The high voltage electrodes were 3 centimeters by 2.5 centimeters by 0.5 centimeters and had a separation distance of approximately 32 centimeters. The high voltage electrodes and the metal members were fabricated from stainless steel. The pulse frequency was maintained at 150 Hz and the pulse duration was initially set to 250 microseconds and gradually lowered to 200 microseconds during the course of a 2 hour run. The high voltage supply was set to 910 volts, drawing a current of between 2.21 and 2.45 amps. The initial temperature was 30° C. and monitored continuously with a pair of thermocouples, one in each side of the tank. After conclusion of the 2 hour run, the temperature of the tank fluid had increased to 60° C.
As with the previously described set of tests, the correlation between electrode size and heat production efficiency was demonstrated by replacing the high voltage electrodes with larger electrodes measuring 9.5 centimeters by 5 centimeters by 0.5 centimeters. The larger electrodes, still operating at a voltage of 910 volts, drew a current of between 1.6 and 1.94 amps. The pulse frequency was still maintained at 150 Hz, however, the pulse duration was lowered from an initial setting of 90 microseconds to 25 microseconds. All other operating parameters were the same as in the previous test. In this test during the course of a 6 hour run, the temperature of the tank fluid increased from 23° C. to 68° C., providing an increase in heat production efficiency of approximately 3 times over that exhibited in the previous test.
As with the previous exemplary embodiment, it will be appreciated that there are numerous minor variations of the electrolytic heating subsystem described above and shown in
In at least one preferred embodiment of the invention, the electrolytic heating subsystem uses a reaction rate controller to help achieve optimal performance of the heating subsystem(s). The rate controller operates by generating a magnetic field within the electrolysis tank, either within the region between the high voltage cathode(s) and the low voltage cathode(s) or metal member(s), or within the region between the high voltage anode(s) and the low voltage anode(s) or metal member(s), or both regions. The magnetic field can either be generated with an electromagnetic coil or coils, or with one or more permanent magnets. The benefit of using electromagnetic coils is that the intensity of the magnetic field generated by the coil or coils can be varied by controlling the current supplied to the coil(s), thus providing a convenient method of controlling the reaction rate.
In the electrolytic heating subsystem illustrated in
Although the subsystem embodiment shown in
The magnetic field rate controller is not limited to use with electrolytic heating subsystems employing both low and high voltage electrodes. For example, the electromagnetic rate controller subsystem can be used with embodiments using high voltage electrodes and metal members as described above and shown in the exemplary embodiment of
As previously noted, although electromagnetic coils provide a convenient means for controlling the intensity of the magnetic field applied to the reactor, permanent magnets can also be used with the electrolytic heating subsystem of the invention, for example when the magnetic field does not need to be variable.
In at least one mode of operation, the system controller is configured to adjust the operating parameters of the electrolytic heating subsystem during operation, for example based on the temperature of the electrolysis medium. This type of control can be used, for example, to insure that the temperature of the electrolytic heating subsystem remains within a preset range, even if the system output varies with age. Typically this type of process modification occurs periodically; for example the system can be configured to execute a system performance self-check every 30 minutes or at some other time interval.
As will be understood by those familiar with the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2,613,902 | Dec 2007 | CA | national |
The present application is a divisional of U.S. patent application Ser. No. 12/313,464, filed 20 Nov. 2008, which, under 35 U.S.C. 119, claims the benefit of the earlier filing date and the right of priority to Canadian Patent Application Serial No. 2,613,902, filed 7 Dec. 2007, the disclosures of which are hereby incorporated by reference for any and all purposes.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12313464 | Nov 2008 | US |
| Child | 13347323 | US |
