U.S. patent application number 13/347323 was filed with the patent office on 2012-05-03 for power generator utilizing a heat exchanger and circulated medium from a pulsed electrolysis system and method of using same.
Invention is credited to Nehemia Davidson.
Application Number | 20120102953 13/347323 |
Document ID | / |
Family ID | 40751125 |
Filed Date | 2012-05-03 |
United States Patent
Application |
20120102953 |
Kind Code |
A1 |
Davidson; Nehemia |
May 3, 2012 |
Power Generator Utilizing a Heat Exchanger and Circulated Medium
from a Pulsed Electrolysis System and Method of Using Same
Abstract
A power generating system (100) and a method of operating the
same is provided, the system utilizing an electrolytic heating
subsystem (103). The electrolytic heating subsystem is a pulsed
electrolysis system that heats a heat transfer medium contained
within a first conduit (109) in thermal communication with the
electrolytic heating subsystem and at least one heat exchanger
(105). A second conduit (117) coupled to the at least one heat
exchanger contains a working fluid. As the working fluid is
circulated through the second conduit and through the heat
exchanger(s), it is heated 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 (119), causing its rotation and, in turn, an electric
generator (121) coupled to the steam turbine.
Inventors: |
Davidson; Nehemia;
(Rosh-Haayin, IL) |
Family ID: |
40751125 |
Appl. No.: |
13/347323 |
Filed: |
January 10, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12313464 |
Nov 20, 2008 |
|
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13347323 |
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Current U.S.
Class: |
60/645 |
Current CPC
Class: |
C25B 9/19 20210101; Y02E
60/36 20130101; C25B 1/04 20130101; F22B 1/021 20130101; Y02P
20/129 20151101; C25B 9/73 20210101; C25B 15/00 20130101; Y02E
20/14 20130101; H05B 3/60 20130101 |
Class at
Publication: |
60/645 |
International
Class: |
F01K 13/00 20060101
F01K013/00; C25B 15/00 20060101 C25B015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 7, 2007 |
CA |
2,613,902 |
Claims
1. A method of generating electricity, the method comprising the
steps of: heating a liquid contained within an electrolysis tank of
an electrolytic heating subsystem, wherein said liquid heating step
further comprises the step of performing electrolysis in said
electrolysis tank of said electrolytic heating subsystem, wherein
said liquid heating step is performed by said electrolytic heating
subsystem; circulating said heated liquid from said electrolysis
tank through a first conduit and through a heat exchanger coupled
to said first conduit; circulating a working fluid through a second
conduit, wherein said second conduit is coupled to said heat
exchanger, said working fluid circulating step further comprising
the steps of heating said working fluid above the boiling point of
the working fluid as the working fluid passes through said heat
exchanger, and generating vapor as said working fluid is heated
above the boiling point of the working fluid; circulating said
vapor through a steam turbine, wherein said vapor circulating step
causes rotation of said steam turbine; and rotating a drive shaft
of a generator, wherein said drive shaft is coupled to said steam
turbine, and wherein said drive shaft rotating step causes said
generator to generate electricity.
2. The method of claim 1, wherein said heated liquid circulating
step further comprises the steps of first circulating said heated
liquid through a first stage of said heat exchanger and second
circulating said heated liquid through a second stage of said heat
exchanger, and wherein said working fluid circulating step further
comprising the steps of first circulating said working fluid
through said second stage of said heat exchanger and second
circulating said working fluid through said first stage of said
heat exchanger.
3. The method of claim 1, wherein said electrolysis performing step
further comprises the steps of: periodically measuring a
temperature corresponding to said electrolytic heating subsystem;
comparing said measured temperature with a preset temperature; and
modifying at least one process parameter of said electrolytic
heating subsystem when said measured temperature is above or below
said preset temperature by more than a preset quantity.
4. The method of claim 1, wherein said electrolysis performing step
further comprises the steps of: periodically measuring a
temperature corresponding to said liquid; comparing said measured
temperature with a preset temperature; and modifying at least one
process parameter of said electrolytic heating subsystem when said
measured temperature is above or below said preset temperature by
more than a preset quantity.
5. The method of claim 1, wherein said electrolysis performing step
further comprises the steps of: periodically measuring a
temperature corresponding to said working fluid; comparing said
measured temperature with a preset temperature; and modifying at
least one process parameter of said electrolytic heating subsystem
when said measured temperature is above or below said preset
temperature by more than a preset quantity.
6. The method of claim 1, said electrolysis performing step further
comprising the steps of: applying a low voltage to at least one
pair of low voltage electrodes contained within said electrolysis
tank of said electrolytic heating subsystem, said at least one pair
of low voltage electrodes fabricated from a first material, said
low voltage applying step further comprising the step of pulsing
said low voltage at a first frequency and with a first pulse
duration applying a high voltage to at least one pair of high
voltage electrodes contained within said electrolysis tank, said at
least one pair of high voltage electrodes fabricated from a second
material, said high voltage applying step further comprising the
step of pulsing said high voltage at said first frequency and with
said first pulse duration, wherein said high voltage pulsing step
is performed simultaneously with said low voltage pulsing step, and
wherein said low voltage electrodes of said at least one pair of
low voltage electrodes are positioned between said high voltage
electrodes of said at least one pair of high voltage electrodes;
and selecting said first material and said second material from the
group consisting of titanium, stainless steel, copper, iron, steel,
cobalt, manganese, zinc, nickel, platinum, palladium, aluminum,
lithium, magnesium, boron, carbon, graphite, carbon-graphite, and
metal hydrides and alloys of titanium, stainless steel, copper,
iron, steel, cobalt, manganese, zinc, nickel, platinum, palladium,
aluminum, lithium, magnesium, boron, carbon, graphite,
carbon-graphite, and metal hydrides.
7. The method of claim 6, further comprising the step of generating
a magnetic field within a portion of said electrolysis tank,
wherein said magnetic field affects a heating rate corresponding to
said heat transfer medium heating step.
8. The method of claim 1, said electrolysis performing step further
comprising the steps of applying a high voltage to at least one
pair of high voltage electrodes contained within said electrolysis
tank, said at least one pair of high voltage electrodes fabricated
from a first material, said high voltage applying step further
comprising the step of pulsing said high voltage at a first
frequency and with a first pulse duration, wherein each pair of
said at least one pair of high voltage electrodes includes at least
one high voltage cathode electrode and at least one high voltage
anode electrode, wherein each high voltage cathode electrode is
positioned within a first region of said electrolysis tank and each
high voltage anode electrode is positioned within a second region
of said electrolysis tank, wherein at least a first metal member of
a plurality of metal members fabricated from a second material is
located within said first region of said electrolysis tank between
said high voltage cathode electrodes and a membrane located within
said electrolysis tank, and wherein at least a second metal member
of said plurality of metal members is located within said second
region of said electrolysis tank between said high voltage anode
electrodes and said membrane, and further comprising the step of
selecting said first material and said second material from the
group consisting of titanium, stainless steel, copper, iron, steel,
cobalt, manganese, zinc, nickel, platinum, palladium, aluminum,
lithium, magnesium, boron, carbon, graphite, carbon-graphite, and
metal hydrides and alloys of titanium, stainless steel, copper,
iron, steel, cobalt, manganese, zinc, nickel, platinum, palladium,
aluminum, lithium, magnesium, boron, carbon, graphite,
carbon-graphite, and metal hydrides.
9. The method of claim 8, further comprising the step of generating
a magnetic field within a portion of said electrolysis tank,
wherein said magnetic field affects a heating rate corresponding to
said heat transfer medium heating step.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] 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.
FIELD OF THE INVENTION
[0002] The present invention relates generally to electric power
generating systems.
BACKGROUND OF THE INVENTION
[0003] 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.
[0004] 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.
[0005] 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.
[0006] Accordingly, what is needed is a steam-electric power plant
that is scalable and environmentally friendly. The present
invention provides such a system.
SUMMARY OF THE INVENTION
[0007] 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.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an illustration of an exemplary embodiment of the
invention;
[0013] FIG. 2 is an illustration of an alternate exemplary
embodiment with multiple heating stages and a single electrolytic
heating subsystem;
[0014] FIG. 3 is an illustration of an alternate exemplary
embodiment with multiple heating stages and multiple electrolytic
heating subsystems;
[0015] FIG. 4 is a detailed view of an embodiment of the
electrolytic heating subsystem;
[0016] FIG. 5 is a detailed view of an alternate embodiment of the
electrolytic heating subsystem shown in FIG. 4;
[0017] FIG. 6 is a detailed view of an alternate embodiment of the
electrolytic heating subsystem shown in FIG. 4 utilizing an
electromagnetic rate controller;
[0018] FIG. 7 is a detailed view of an alternate embodiment of the
electrolytic heating subsystem shown in FIG. 5 utilizing an
electromagnetic rate controller as shown in FIG. 6;
[0019] FIG. 8 is a detailed view of an alternate embodiment of the
electrolytic heating subsystem shown in FIG. 6 utilizing a
permanent magnet rate controller;
[0020] FIG. 9 is a detailed view of an alternate embodiment of the
electrolytic heating subsystem shown in FIG. 7 utilizing a
permanent magnet rate controller; and
[0021] FIG. 10 illustrates a mode of operation in which the
electrolytic heating subsystem is periodically optimized.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0022] FIG. 1 is an illustration of an exemplary system 100 in
accordance with the invention. System 100 is comprised of three
primary subsystems; electric power generation subsystem 101, pulsed
electrolytic heating subsystem 103, and heat exchanger subsystem
105. The system can be scaled to allow optimization for different
power output requirements.
[0023] 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.degree.-250.degree. C., more preferably on the order of
250.degree.-350.degree. C., and still more preferably on the order
of 350.degree.-500.degree. C. It some embodiments, the system is
maintained at even higher temperatures.
[0024] 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.
[0025] 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.
[0026] 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.
[0027] 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.
[0028] 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.
[0029] FIG. 2 schematically illustrates the application of the
present invention to a three stage heating system. It will be
appreciated that other configurations and/or different numbers of
heating stages can also be used with the invention. In this
embodiment the working fluid first passes through a pre-heater 201
(i.e., first heat exchanger stage). Preferably pre-heater 201 heats
the working fluid up to a temperature below the boiling point of
the working fluid. Next the working fluid passes through the
central heater 203 (i.e., second heat exchanger stage). Heater 203
heats the working fluid to a temperature above its boiling point,
thereby forming vapor. As the vapor remains in contact with the
surface of the working fluid, the vapor is saturated and therefore
unable to be superheated. Accordingly in at least one embodiment of
the invention the saturated vapor is extracted from heat exchanger
stage 203 and further heated within super-heater 205 (i.e., third
heat exchanger stage). As illustrated in FIG. 2, the highest
temperature electrolysis medium is used within super-heater 205.
Due to the removal of heat from the electrolysis medium as it
passes through each heating stage, the electrolysis medium is at
it's lowest temperature as it passes through pre-heater stage 201.
Although as previously noted, the degree of system monitoring can
be varied, preferably in this embodiment the temperature of the
electrolysis medium is monitored before and after each heating
stage by temperature monitors 207-210. Similarly, in the preferred
embodiment the temperature of the working fluid before and after
each heating stage is monitored by monitors 211-214.
[0030] Multi-stage heating systems can also be used with multiple
electrolytic heating subsystems as shown in the exemplary
embodiment of FIG. 3. In system 300 pre-heater stage 201 is coupled
to a first electrolytic heating subsystem 301, central heater stage
203 is coupled to a second electrolytic heating subsystem 302, and
super-heater stage 205 is coupled to a third electrolytic heating
subsystem 303. It will be appreciated that, if desired, multiple
heating stages can be coupled to one or more of the multiple
electrolytic heating subsystems, thus combining features
illustrated in FIGS. 2 and 3. One advantage of using multiple
electrolytic heating subsystems is that each of them can be
optimized for the desired temperature for the corresponding heat
exchanger (s). Preferably temperature monitors are included in each
of the electrolytic heating subsystems (i.e., monitors 305-307) and
at the inlet and outlet lines to each of the heat exchangers (i.e.,
monitors 309-314). The use of multiple electrolytic heating
subsystems also adds to the number of circulation pumps (i.e.,
pumps 315-317) and control valves (i.e., valves 319-321) required
to operate the system in accordance with the preferred mode.
[0031] 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 FIGS. 1 and 2, or for
systems utilizing multiple electrolytic heating subsystems as shown
in FIG. 3.
[0032] FIG. 4 is an illustration of a preferred embodiment of an
electrolytic heating subsystem 400. Note that in FIGS. 4-9 only a
portion of conduits 109 are shown. Additionally, while FIGS. 1-3
only show a single pair of conduits 109 for tank 111, preferably
each region of the electrolysis tank includes an inlet and an
outlet conduit 109 as shown in FIG. 4, thus insuring that the
electrolysis medium circulated through the heat exchanger(s) is
coupled to both regions. As previously noted, preferably a control
valve is associated with conduit 109. In the embodiment shown in
FIG. 4, each of the conduits 111 coupled to the two regions of the
electrolysis tank 111 include a control valve 401, although it will
be appreciated that the system can operate with fewer valves.
Control valve or valves 401 are preferably coupled to controller
127 as shown.
[0033] 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 (H.sub.2O), deuterated water (deuterium
oxide or D.sub.2O), tritiated water (tritium oxide or T.sub.2O),
semiheavy water (HDO), heavy oxygen water (H.sub.2.sup.18O or
H.sub.2.sup.17O) or any other water containing an isotope of either
hydrogen or oxygen, either singly or in any combination thereof
(for example, a combination of H.sub.2O and D.sub.2O).
[0034] 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.
[0035] 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.
[0036] 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.degree.-250.degree. C., more preferably on
the order of 250.degree.-350.degree. C., and still more preferably
on the order of 350.degree.-500.degree. 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.
[0037] Replenishment of medium 107 can be through one or more
dedicated lines. FIG. 4 shows a portion of one such conduit,
conduit 409, coupled to one of the regions of tank 111.
Alternately, a replenishment conduit can be coupled to both regions
of tank 111 (not shown). Alternately, the replenishment conduit can
be coupled to the one or more of conduits 109. Although medium
replenishment can be performed manually, preferably replenishment
is performed automatically, for example using system controller 127
and flow valve 411 within line 409. Replenishment can be performed
periodically or continually at a very low flow rate. If periodic
replenishment is used, it can either be based on the period of
system operation, for example replenishing the system with a
predetermined volume of medium after a preset number of hours of
operation, or based on the volume of medium within tank 111, the
volume being provided to controller 127 using a level monitor 413
within the tank or other means. In at least one preferred
embodiment system controller 127 is also coupled to a monitor 415,
monitor 415 providing either the pH or the resistivity of liquid
107 within the electrolysis tank, thereby providing means for
determining when additional electrolyte needs to be added. In at
least one embodiment and as previously noted, preferably system
controller 127 is also coupled to a temperature monitor 131,
monitor 131 providing the temperature of the electrolysis
medium.
[0038] 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 FIG. 4, each type of
electrode includes a single pair of electrodes.
[0039] 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.
[0040] 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.
[0041] 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.
[0042] 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.
[0043] 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 FIG. 4, low
voltage power supply 421, high voltage power supply 427 and pulse
generator 429 are all connected to system controller 127, thus
allowing controller 127 to control the amount of heat generated by
the electrolytic heating subsystem. It will be appreciated that
both power supplies and the pulse generator do not have to be
connected to system controller 127 to provide heat generation
control. For example, only one of the power supplies and/or the
pulse generator can be connected to controller 127.
[0044] 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 FIG. 4 that can be used with the
invention. For example, and as previously noted, alternate
configurations can utilize tanks of different size and/or shape,
different electrolytic solutions, and a variety of different
electrode configurations and materials. Exemplary alternate
electrode configurations include, but are not limited to, multiple
low voltage cathodes, multiple low voltage anodes, multiple high
voltage cathodes, multiple high voltage anodes, multiple low
voltage electrode pairs combined with multiple high voltage
electrode pairs, electrodes of varying size or shape (e.g.,
cylindrical, curved, etc.), and electrode pairs of varying
orientation (e.g., non-parallel faces, pairs in which individual
electrodes are not positioned directly across from one another,
etc.). Additionally, alternate configurations can utilize a variety
of input powers, pulse frequencies and pulse durations as
previously noted.
[0045] 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.degree. 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.degree. C.
[0046] 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.degree. C. to 69.degree. 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.
[0047] FIG. 5 is an illustration of a second exemplary embodiment
of the electrolytic heating subsystem, this embodiment using a
single type of electrodes. Subsystem 500 is basically the same as
subsystem 400 shown in FIG. 4 with the exception that low voltage
electrodes 417/419 have been replaced with a pair of metal members
501/503; metal member 501 interposed between high voltage electrode
423 and membrane 403 and metal member 503 interposed between high
voltage electrode 425 and membrane 403. The materials comprising
metal members 501/503 are the same as those of the low voltage
electrodes. Preferably the surface area of the faces of members 501
and 503 is a large percentage of the cross-sectional area of tank
111, typically on the order of at least 40 percent, and often
between approximately 70 percent and 90 percent of the
cross-sectional area of tank 111. Preferably the separation between
members 501 and 503 is between 0.1 millimeters and 15 centimeters.
In at least one embodiment the separation between the metal members
is between 0.1 millimeters and 1 millimeter. In at least one other
embodiment the separation between the metal members is between 1
millimeter and 5 millimeters. In at least one other embodiment the
separation between the metal members is between 5 millimeters and 2
centimeters. In at least one other embodiment the separation
between the metal members is between 5 centimeters and 8
centimeters. In at least one other embodiment the separation
between the metal members is between 10 centimeters and 12
centimeters. The preferred ranges for the size of the high voltage
electrodes as well as the high voltage power, pulse frequency and
pulse duration are the same as in the exemplary subsystem shown in
FIG. 4 and described above.
[0048] 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.degree. 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.degree. C.
[0049] 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.degree. C. to
68.degree. C., providing an increase in heat production efficiency
of approximately 3 times over that exhibited in the previous
test.
[0050] 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 FIG. 5
that can be used with the invention. For example, and as previously
noted, alternate configurations can utilize tanks of different size
and/or shape, different electrolytic solutions, and a variety of
different electrode/metal member configurations and materials.
Exemplary alternate electrode/metal member configurations include,
but are not limited to, multiple sets of metal members, multiple
high voltage cathodes, multiple high voltage anodes, multiple sets
of metal members combined with multiple high voltage cathodes and
anodes, electrodes/metal members of varying size or shape (e.g.,
cylindrical, curved, etc.), and electrodes/metal members of varying
orientation (e.g., non-parallel faces, pairs in which individual
electrodes are not positioned directly across from one another,
etc.). Additionally, alternate configurations can utilize a variety
of input powers, pulse frequencies and pulse durations.
[0051] 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.
[0052] FIG. 6 provides an exemplary embodiment of an electrolytic
heating subsystem 600 that includes an electromagnetic rate
controller. It should be understood that the electromagnetic rate
controller shown in FIGS. 6 and 7, or the rate controller using
permanent magnets shown in FIGS. 8 and 9, is not limited to a
specific tank/electrode configuration. For example, electrolysis
tank 601 of system 600 is cylindrically-shaped although the tank
could utilize other shapes such as the rectangular shape of tank
111. As in the previous embodiments, the electrolytic heating
subsystem includes a membrane (e.g., membrane 603) separating the
tank into two regions, a pair of gas outlets (e.g., outlets
605/607), inlet and outlet conduits 109 (one pair per region in the
exemplary embodiment illustrated in FIG. 6) to allow the
electrolysis medium to be circulated through the heat exchanger,
and preferably flow control valves (e.g., valves 401) coupled to
the system controller 127. A separate replenishment conduit can be
used as previously illustrated in FIGS. 4 and 5, although such a
conduit is not shown in FIGS. 6-9, thereby simplifying the
illustration. Preferably the system also includes a water level
monitor (e.g., monitor 609), a pH or resistivity monitor (e.g.,
monitor 611), and a temperature monitor 125. This embodiment,
similar to the one shown in FIG. 4, utilizes both low voltage and
high voltage electrodes. Specifically, subsystem 600 includes a
pair of low voltage electrodes 613/615 and a pair of high voltage
electrodes 617/619.
[0053] In the electrolytic heating subsystem illustrated in FIG. 6,
a magnetic field of controllable intensity is generated between the
low voltage and high voltage electrodes within each region of tank
601. Although a single electromagnetic coil can generate fields
within both tank regions, in the illustrated embodiment the desired
magnetic fields are generated by a pair of electromagnetic coils
621/623. As shown, electromagnetic coil 621 generates a magnetic
field between the planes containing low voltage electrode 613 and
high voltage electrode 617 and electromagnetic coil 623 generates a
magnetic field between the planes containing low voltage electrode
615 and high voltage electrode 619. Electromagnetic coils 621/623
are coupled to a controller 625 which is used to vary the current
through coils 621/623, thus allowing the strength of the magnetic
field generated by the electromagnetic coils to be varied as
desired. As a result, the rate of the reaction driven by the
electrolysis system, and thus the amount of heat generated by the
subsystem, can be controlled. In particular, increasing the
magnetic field generated by coils 621/623 decreases the reaction
rate. Accordingly, a maximum reaction rate is achieved with no
magnetic field while the minimum reaction rate is achieved by
imposing the maximum magnetic field. It will be appreciated that
the exact relationship between the magnetic field and the reaction
rate depends on a variety of factors including reaction strength,
electrode composition and configuration, voltage/pulse
frequency/pulse duration applied to the electrodes, electrolyte
concentration, and achievable magnetic field, the last parameter
dependent primarily upon the composition of the coils, the number
of coil turns, and the current available from controller 625.
[0054] Although the subsystem embodiment shown in FIG. 6 utilizes
coils that are interposed between the low voltage electrode and the
high voltage electrode planes, it will be appreciated that the
critical parameter is to configure the system such that there is a
magnetic field, preferably of controllable intensity, between the
low voltage and high voltage electrode planes. Thus, for example,
if the coils extend beyond either, or both, the plane containing
the low voltage electrode(s) and the plane controlling the high
voltage electrode(s), the system will still work as the field
generated by the coils includes the regions between the low voltage
and high voltage electrodes. Additionally it will be appreciated
that although the embodiment shown in FIG. 6 utilizes a single
controller 625 coupled to both coils, the system can also utilize
separate controllers for each coil (not shown). Similarly, while
the illustrated subsystem utilizes dual coils, the invention can
also use a single coil to generate a single field which affects
both tank regions, or primarily affects a single tank region.
Additionally it will be appreciated that the electromagnetic coils
do not have to be mounted to the exterior surface of the tank as
shown in FIG. 6. For example, the electromagnetic coils can be
integrated within the walls of the tank, or mounted within the
tank. By mounting the electromagnetic coils within, or outside, of
the tank walls, coil deterioration from electrolytic erosion is
minimized.
[0055] 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 FIG. 5. FIG. 7 is an illustration of
an exemplary embodiment based on the embodiment shown in FIG. 6,
replacing low voltage electrodes 613/615 with metal members
701/703, respectively. As with the electromagnetic rate controller
used with the dual voltage system, it will be appreciated that
configurations using high voltage electrodes and metal members can
utilize internal electromagnetic coils, electromagnetic coils
mounted within the tank walls, and electromagnetic coils mounted
outside of the tank walls. Additionally, and as previously noted,
the electromagnetic rate controller is not limited to a specific
tank and/or electrode configuration.
[0056] 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. FIGS.
8 and 9 illustrate embodiments based on the configurations shown in
FIGS. 6 and 7, but replacing coils 621 and 623 with permanent
magnets 801 and 803, respectively. Note that in the view of FIG. 8,
only a portion of electrode 613 is visible while none of electrode
619 is visible. Similarly in the view of FIG. 9, only a portion of
metal member 701 is visible while none of electrode 619 is
visible.
[0057] 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.
[0058] FIG. 10 illustrates a preferred method of modifying the
output of the electrolytic heating subsystem. As shown, during
system operation (step 1001) the system controller periodically
performs a self-check (step 1003). The first step of the self-check
process is to determine the temperature of the selected region of
the system (step 1005). As previously noted, typically the system
is configured to perform the self-check process on the basis of the
monitored temperature of the electrolysis fluid, although the
temperature of other regions/components can also be used. The
measured temperature is then compared to a preset temperature or
temperature range (step 1007). If the temperature is acceptable
(step 1009), for example within the preset temperature range, the
system simply goes back to standard operation until the system
determines that it is time for another system check. If the
measured temperature is unacceptable (step 1011), for example if it
falls outside of the preset range, the electrolysis process is
modified (step 1013). During the electrolysis process modification
step, i.e., step 1013, one or more process parameters are varied.
Exemplary process parameters include pulse duration, pulse
frequency, system power cycling, electrode voltage, and, if the
system includes an electromagnetic rate control system, the
intensity of the magnetic field. Preferably during the electrolysis
modification step, the system controller modifies the process in
accordance with a series of pre-programmed changes, for example
altering the pulse duration in 10 microsecond steps until the
desired temperature is reached. Since varying the electrolysis
process does not have an immediate affect on the monitored
temperature, preferably after making a system change, a period of
time is allowed to pass (step 1015) before determining if further
process modification is required, thus allowing the system to reach
equilibrium, or close to equilibrium. During the process, the
system controller continues to monitor the temperature of the
selected region/material (step 1017) and compare that temperature
to the preset temperature/temperature range in order to determine
if further modification is required (step 1019). Once the
temperature reaches an acceptable level (step 1021), the system
goes back to standard operation.
[0059] 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.
* * * * *