(12) United States Patent
`(10) Patent N0.:
`US 6,171,469 B1
`
`Hough et al.
`(45) Date of Patent:
`*Jan. 9, 2001
`
`US006171469B1
`
`(54) METHOD AND APPARATUS FOR
`INCREASING THE OXYGEN CONTENT OF
`WATER
`
`(75)
`
`Inventors: Gary S. Hough, Woodinville; Troy T.
`Johnson, Bellevue, both of WA (US)
`
`(73) Assignee: H20 Technologies, Ltd., Milwaukie,
`OR (US)
`
`(*) Notice:
`
`This patent issued on a continued pros-
`ecution application filed under 37 CFR
`1.53(d), and is subject to the twenty year
`patent
`term provisions of 35 U.S.C.
`154(a)(2).
`
`Under 35 U.S.C. 154(b), the term of this
`patent shall be extended for 0 days.
`
`(21) Appl. N0.: 08/744,706
`
`(22)
`
`Filed:
`
`Oct. 31, 1996
`
`Int. Cl.7 ...................................................... C02F 1/461
`(51)
`
`(52) U.S. Cl.
`205/743; 205/744; 205/755;
`205/756; 204/2292; 204/2294; 204/2751
`(58) Field of Search ..................................... 205/743, 744,
`205/755, 756; 204/229, 275, 275.1, 229.2,
`229.4
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`2,468,357
`2,864,750
`3,095,365 *
`3,523,891
`3,654,119
`3,728,245
`3,819,504
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`3,925,176
`3,943,044
`4,017,375
`
`4/1949 Brown .................................. 204/248
`..
`12/1958 Hughes, Jr. et al.
`204/149
`
`.. 204/229
`6/1963 Green .....
`
`8/1970 Mehl ........... 210/44
`4/1972 White et al.
`204/228
`
`4/1973 Preis et a1.
`.
`204/275
`6/1974 Bennett
`..
`204/289
`.. 204/228
`2/1975 Phipps
`204/152
`12/1975 0km .........
`3/1976 Fenn, 111 et al.
`204/149
`
`4/1977 Pohto ................................... 204/255
`
`
`
`.
`
`4,119,517
`4,132,620
`4,160,716
`4,180,445
`4,312,736
`
`................................. 204/229
`10/1978 Hengst
`1/1979 Nidola et al.
`. 204/242
`7/1979 Wiseman ..........
`. 204/270
`
`..
`12/1979 Bennett et a1.
`. 204/129
`........................ 204/255
`1/1982 Menth et a1.
`
`(List continued on next page.)
`FOREIGN PATENT DOCUMENTS
`
`W087/01690 *
`W0 94/00216
`WO95/21795 *
`
`3/1987 (W0) ................................ 205/756
`1/1994 (W0).
`8/1995 (W0).
`OTHER PUBLICATIONS
`
`The Advanced Water Systems Incorporated, company bro-
`chure regarding information on various products to improve
`water quality, different types of water systems and current
`technology, Sep. 30, 1993.
`
`Primary Examiner—Arun S. Phasge
`(74) Attorney, Agent, or Firm—SEED IP Law Group PLLC
`
`(57)
`
`ABSTRACT
`
`Amethod and apparatus for increasing the oxygen content of
`water have been shown and described. Avolume of water is
`
`passed between the electrodes of an electrolytic cell, a
`portion of the volume of water converting to dissolved
`oxygen. A desired level of dissolved oxygen is selected, and
`the number of times the volume of water must flow through
`the electrolytic cell
`to ensure that the volume of water
`contains the selected percentage of dissolved oxygen is also
`selected. The volume of water is then forced through the cell
`the selected number of times, such that the volume of water
`contains the desired percentage of dissolved oxygen. The
`electrolytic cell is in fluid communication with a tank and a
`pump, the pump drawing the volume of water from the tank
`and forcing it through the electrolytic cell and back into the
`tank. The volume of water is thereby recirculated through
`the electrolytic cell by the pump for the selected number of
`times.
`
`9 Claims, 4 Drawing Sheets
`
`1 7
`
`/ \
`/ \sxf
`
`
`
`
`
`
`
`147
`
`30
`
`
`
` 1“3:5
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`W
`
`
`25 j
`
`[5/
`
`Tennant Company
`Exhibit 1141
`
`Tennant Company
`Exhibit 1141
`
`

`

`US 6,171,469 B1
`
`Page 2
`
`US. PATENT DOCUMENTS
`
`
`5/1983 R615 6‘ 8L
`~~~~~~~~~~~~~~~~~~ 205/743
`12/1983 Frame
`~~~~~~~~~~~~~~~~~~ 204/228
`1/1984 Neymeyer ............................ 204/270
`
`. 204/149
`3/1984 Branchick et al.
`5/1984 Miller ................................... 204/149
`7/1985 LaConti et a1.
`...................... 204/265
`
`2/1986 Paniagua ~-
`~ 204/229
`11/1986 Umehara .............................. 204/149
`1/1987 Staab et al.
`.................. 204/2'58
`
`8/1988 Gram et a1.
`204/95
`
`11/1988 Dahlgren .....
`. 204/149
`
`11/1988 Langeland et a .
`.................... 204/‘95
`
`493859973 *
`4,419,206
`4,425,216
`4,436,601
`4,451,341
`4,528,083
`45727775
`4,623,436
`4,639,303
`4,761,208
`4,781,805
`4,783,246
`
`4,784,735
`4,790,914
`4,797,182
`4,839,007
`4,917,782
`4,936,979
`5,062,940
`5,292,412
`5,324,398
`5,328,584
`5,389,214
`5,427,667
`
`11/1988 Sorenson ................................ 204/98
`12/1988 Sorenson
`204/98
`
`.......................... 204/14.1
`1/1989 Beer et a1.
`6/1989 K6tz et a1.
`........................... 240/149
`4/1990 Davies ..
`. 204/152
`6/1990
`210/85
`11/199 1
`204/228
`3/1994
`. 204/149
`6/1994 Erickson et a1.
`..................... 204/149
`7/1994 Erickson et a1.
`..................... 204/229
`2/1995 Erickson et a1.
`.
`204/149
`
`6/1995 Bakhir et al.
`204/260
`
`
`
`* Cited by examiner
`
`

`

`US. Patent
`
`Jan. 9, 2001
`
`Sheet 1 0f4
`
`US 6,171,469 B1
`
`
`
`

`

`US. Patent
`
`Jan. 9, 2001
`
`Sheet 2 0f 4
`
`US 6,171,469 B1
`
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`

`

`US. Patent
`
`Jan. 9, 2001
`
`Sheet 3 0f 4
`
`US 6,171,469 B1
`
`
`
`
`
`
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`
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`
`

`

`US. Patent
`
`Jan. 9, 2001
`
`Sheet 4 0f4
`
`US 6,171,469 B1
`
`32
`
`drawing a volume of water from a tank
`
`53
`
`34
`
`
`
`
`
`
`
`pumping the volume of water through an
`electrolytic cell and back into the tank
`
` selecting a number of
`times the volume of
`water must
`flow though the electrolytic cell
`to ensure that
`the volume of water contains
`
`a selected percentage of dissolved oxygen
`
`
`
`
`
`pumping the water from the tank
`through the electrolytic cell
`the selected
`
`
`number of
`times
`
`
`
`35
`
`Hg. 4
`
`

`

`US 6,171 ,469 B1
`
`1
`METHOD AND APPARATUS FOR
`INCREASING THE OXYGEN CONTENT OF
`WATER
`
`TECHNICAL FIELD
`
`This invention relates to the electrolytic generation of
`oxygen, and more particularly, to an improved method and
`apparatus for increasing the dissolved oxygen content of
`water.
`
`BACKGROUND OF THE INVENTION
`
`Many benefits may be obtained through the use of water
`containing an elevated quantity of dissolved oxygen. For
`example, certain studies have shown that animals such as
`chickens and turkeys grow heavier for a given grain con-
`sumption if their drinking water has elevated oxygen levels.
`Increased levels of oxygen in water also act to purify the
`water, killing a variety of biological and chemical
`contaminants, as is known in the art. Further, it is believed
`that humans may obtain certain health benefits by consum-
`ing oxygenated water.
`The oxygen content of water may be increased via
`electrolysis, a process that
`is well known in the art.
`Typically, current is supplied to a cathode and an anode
`positioned in a water solution. The passage of electricity
`through the solution splits the water molecule causing the
`formation of hydrogen and oxygen gas. The hydrogen tends
`to bubble out of solution, whereas a certain quantity of the
`oxygen molecules are trapped by the water molecules and
`remain in solution, thereby increasing the dissolved oxygen
`content of the water.
`
`Currently available systems for oxygenating water with
`electrolytic cells may not reach desired levels of dissolved
`oxygen, nor do they function as efficiently as desired.
`Accordingly, there is a need in the art for an improved
`system for increasing the dissolved oxygen content of water
`to desired levels at an improved efficiency and speed.
`SUMMARY OF THE INVENTION
`
`invention provides an improved
`the present
`Briefly,
`method and apparatus for increasing the oxygen content of
`water. The oxygenated water may then be used for a variety
`of purposes.
`In a preferred embodiment, a volume of water is passed
`between the electrodes of an electrolytic cell to which a
`current is applied. The water is recirculated, such that a
`given volume of water is ensured of passing between the
`electrodes a selected number of times. During each pass
`through the cell, some percentage of the volume of water
`turns into dissolved oxygen. In a preferred embodiment, the
`volume of water is passed between the electrodes a selected
`number of times such that the volume of water contains a
`
`desired amount of dissolved oxygen.
`The number of passes is selected to reach the desired
`oxygen level as efliciently as possible. According to prin—
`ciples of the present invention, after a selected number of
`passes, additional passes only increase the oxygen level
`slightly. For example, after the same volume of a selected
`water sample has circulated 14—16 times through the cell, it
`reaches a desired oxygen level. While additional circulation
`of the same volume of water does increase the oxygen level,
`it is only a modest increase. According to one alternative
`embodiment, the preferred number of passes for a particular
`volume of water varies with the particular properties of the
`water. As will be appreciated, water with a high iron content
`
`10
`
`15
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`may require a different number of passes to reach the
`preferred dissolved oxygen level than soft water, hard water,
`slightly salty water, or the like. The differences of mineral
`and salt content of water from various sources is so great
`with even slight variations affecting the results, that a test is
`preferably conducted to determine the preferred number of
`passes for each particular water source. After the water
`source has been tested and the correct number of passes
`selected, then the system can be set to ensure that the desired
`number of passes occur before water is discharged by the
`system.
`
`For example, in one embodiment, the electrolytic cell has
`eight electrodes, each electrode having a length of 6 inches
`and awidth of 1 .5 inches. A current of 1 .5 amperes is applied
`to the electrodes, and a volume of water flows past the
`electrodes at a rate of 3.8 gallons per minute. For the volume
`of water to reach a desired dissolved oxygen content of
`13717 parts per million (ppm), the volume of water is passed
`between the electrodes 15—55 times. The water is recircu-
`lated in this manner until the volume of water has completed
`the specified number of passes through the cell.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a front elevational view illustrating a system
`provided in accordance with a preferred embodiment of the
`present invention.
`FIG. 2A is a partial cross-sectional elevational view of an
`exemplary electrolytic cell used in the system illustrated in
`FIG. 1.
`
`FIG. 2B is a top plan view of the electrolytic cell
`illustrated in FIG. 2A.
`FIG. 2C is a cross-sectional elevational view of an
`alternative, exemplary electrolytic cell.
`FIG. 3 is an enlarged, schematic illustration of a volume
`of water being treated in accordance with a preferred
`embodiment of the present invention.
`FIG. 4 is a schematic illustration of the steps of a preferred
`embodiment of the present invention.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`As illustrated in FIG. 1, an apparatus 10 includes an
`electrolytic cell 12 in series fluid communication with a tank
`26 that holds a volume of water 16. Both the tank 26 and
`electrolytic cell 12 are in series fluid communication with a
`pump 18.
`All water that exits from the tank 20 must pass through the
`cell 12. The water is returned to the top of the cell and drawn
`from the bottom so that generally most of the water passes
`through the cell before any of the water passes through the
`cell a second time. While there may be some mixing as the
`water is returned so that there is a possibility that some small
`volume of water will pass through the cell a second time
`before some has passed through once, the tank and outlet,
`inlet and pump are positioned to maximize the series flow of
`each volume of water.
`
`FIGS. 2A and 2B show an electrolytic cell 12 for treating
`water to increase the dissolved oxygen within the water. An
`alternative electrolytic cell is illustrated in FIG. 2C. Two
`examples of an electrolytic cell are provided for background
`purposes. However, it is to be understood that any one of the
`many suitable electrolytic cells for generating dissolved
`oxygen in water are acceptable.
`
`

`

`US 6,171 ,469 B1
`
`3
`As illustrated in FIG. 2, the electrolytic cell 12 includes a
`plurality of electrodes 20. The electrodes may be made of a
`variety of material such as nickel, stainless steel, or hastaloy;
`however,
`in a preferred embodiment,
`they are made of
`titanium. Any acceptable coating of the type known in the art
`is acceptable. The electrodes are coupled to a source 14 of
`electrical current, such that as a volume of water flows
`through the electrolytic cell in the direction illustrated by
`reference arrow 30, electrolysis occurs, generating hydrogen
`and oxygen. The hydrogen bubbles out of solution, while a
`certain amount of the oxygen remains trapped by the volume
`of water,
`increasing the dissolved oxygen content of the
`volume of water.
`
`In a preferred embodiment of the present invention, a
`specified volume of water 16 reaches a selected content level
`of dissolved oxygen by passing through the electrolytic cell
`a selected number of times. As illustrated in FIG. 3, every
`time a selected volume of water 16 passes between two
`electrodes 20 along the length 22 of the electrodes, a portion
`of the volume of water converts from water to dissolved
`
`oxygen. The volume of water is passed through the cell a
`selected number of times, such that a specified amount of the
`given volume of water contains a desired percentage of
`dissolved oxygen. The volume of water 16 illustrated in FIG.
`3 contains some given percentage of water molecules and
`some given percentage of dissolved oxygen before the first
`pass. After the first pass, the percentage of water molecules
`in that volume has decreased and the percentage of dissolved
`oxygen has increased. The ratio continues to change with
`each pass of the volume of water. After a selected number of
`passes, the dissolved oxygen is sufficiently high that it is
`usable for the desired purpose and the water is provided at
`the outlet for use by the user.
`
`In operation, therefore, as illustrated in FIGS. 1 and 4, the
`pump draws a volume of water from the tank, step 32, and
`forces it through the electrolytic cell, step 33, in the direction
`indicated by reference arrow 30. The water then flows from
`the electrolytic cell back into the tank. The number of times
`the volume of water must flow through the cell to ensure that
`the volume of water contains a desired percentage of dis-
`solved oxygen has been previously selected in most
`embodiments, so that step 34 is not present. The water will
`circulate the preset number of times and then is ready for
`use. The number of particle passes is automatically
`controlled, such as with a timer, and the volume of water is
`forced to flow through the cell the selected number of times,
`step 35. However, in some embodiments, the user or opera-
`tor will select the desired number of particle passes, step 34,
`and the water will circulate the selected time.
`
`In a preferred embodiment, a water sample from a given
`source is tested to determine the characteristics of the water.
`
`For example, if the water has a relatively high salt content,
`the water will be more conductive, and will reach a desired
`dissolved oxygen level
`in fewer passes. The system is
`therefore calibrated by testing the sample of water to deter-
`mine the number of passes through the cell required to reach
`a desired dissolved oxygen content in an efficient manner.
`The system is then set to provide the proper number of
`particle passes to achieve the desired dissolved oxygen
`level.
`
`One example is illustrated in Table 1 below. A given water
`sample has an initial dissolved oxygen content of 8.5 ppm.
`In the table, the number of particle passes has been rounded
`to the nearest whole number.
`
`5
`
`10
`
`15
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`
`TABLE 1
`
`No. of
`Passes
`
`5
`10
`14
`19
`2
`2
`34
`39
`43
`48
`53
`58
`63
`68
`
`Elapsed Time
`sec
`0
`20
`40
`60
`80
`100
`120
`140
`160
`180
`200
`220
`240
`260
`280
`
`Dissolved
`Oxygen (D.O.)
`ppm
`8.5
`9.7
`10.8
`12.5
`13.8
`14.2
`15.1
`15.5
`15.9
`16.5
`16.7
`17.1
`17.1
`17.9
`18.1
`
`% Change
`in DD.
`
`14.12
`11.34
`15.74
`10.40
`2.90
`6.34
`2.65
`2.58
`3.77
`1.21
`2.40
`0.00
`4.68
`1.12
`
`In this example, the volume of water of 1000 ml flows at
`3.8 gallons per minute (gpm) through an electrolytic cell
`having eight electrodes, each electrode being a flat plate
`having a length of six inches and a width of one-and-a-half
`inches of the type shown in FIGS. 1A and 1B. A current of
`1.8 amps is applied to the cell. It is possible to increase the
`dissolved oxygen content by 82%, up to 15.5 ppm, in 34
`passes. Although running the sample through the cell an
`addition 34 times will
`increase the dissolved oxygen
`content, it does so only slightly, namely by 17% to 18.1 ppm
`dissolved oxygen. If the user is primarily concerned with
`insuring that the dissolved oxygen content falls within a
`selected range, for example, 13—17 ppm,
`the number of
`passes will be selected based on how many are required to
`achieve a dissolved oxygen content of 13 ppm and a
`dissolved oxygen content of 17 ppm. In example 1, the
`number of passes required to achieve this range of dissolved
`oxygen is 16—52 passes. As can be seen from the data in
`Table 1, although running the volume of water through the
`cell for additional passes increases the dissolved oxygen
`content slightly, the percent change is small, and does not
`justify the additional energy input
`to the system.
`Alternatively, if a user’s primary concern is maximizing the
`increase in dissolved oxygen for a given energy input, the
`system would be designed to stop between 19 and 24 passes,
`which is where a significant decrease in percent change of
`dissolved oxygen occurs. It will of course be understood that
`the desire for a selected dissolved oxygen content and a
`desire for efficiency may both be met, and weighted accord-
`ing to the particular user and desired application.
`
`Similar results were obtained in separate tests, illustrated
`in Tables 2 and 3 below.
`
`TABLE 2
`
`No. of
`Passes
`
`5
`10
`14
`19
`2
`2
`34
`39
`
`Elapsed Time
`sec
`0
`20
`40
`60
`80
`100
`120
`140
`160
`
`Dissolved
`Oxygen (D.O.)
`ppm
`9.2
`9.9
`11.3
`13.3
`13.7
`14.2
`15.2
`15.9
`16.6
`
`% Change
`in DD.
`
`7.61
`14.14
`17.70
`3.01
`3.65
`7.04
`4.61
`4.40
`
`

`

`US 6,171,469 B1
`
`5
`
`TABLE 2-continued
`
`Elapsed Time
`sec
`180
`200
`220
`240
`260
`280
`
`Dissolved
`Oxygen (D.O.)
`ppm
`17
`17.2
`17.7
`18.1
`18.4
`18.9
`
`TABLE 3
`
`Elapsed Time
`sec
`0
`20
`40
`60
`80
`100
`120
`140
`160
`180
`200
`220
`240
`260
`280
`
`Dissolved
`Oxygen (D.O.)
`ppm
`9.2
`9.9
`11.1
`12.8
`13.9
`14.5
`15.4
`15.8
`16.3
`16.8
`17.2
`17.6
`17.8
`17.9
`18.5
`
`% Change
`in DD.
`2.41
`1.18
`2.91
`2.26
`1.66
`2.72
`
`% Change
`in DD.
`
`7.61
`12.12
`15.32
`8.59
`4.32
`6.21
`2.60
`3.16
`3.07
`2.38
`2.33
`1.14
`0.56
`3.35
`
`No. of
`Passes
`43
`48
`53
`58
`63
`68
`
`No. of
`Passes
`
`5
`10
`14
`19
`24
`29
`34
`39
`43
`48
`53
`58
`63
`68
`
`As illustrated in Table 2, if a dissolved oxygen content of
`13—17 ppm is desired, the volume of water is passed through
`the electrolytic cell 17—44 times. Beyond 44 passes,
`the
`percent increase in dissolved oxygen is substantially less
`significant than the increase in dissolved oxygen achieved
`up to that point. If a desired dissolved oxygen content is in
`a lower range, or efficiency is the primary concern of the
`user, the user may choose to stop processing the water at
`approximately 20 passes, where the percent change of
`dissolved oxygen drops off. Similar results are illustrated in
`Table 3. Therefore, for every sample of water processed in
`accordance with the present invention, there is a point of
`diminishing returns, where a slight increase of dissolved
`oxygen content may not justify the required input of energy.
`The system provided in accordance with the present inven-
`tion is therefore calibrated to reach a desired dissolved
`
`10
`
`15
`
`30
`
`35
`
`40
`
`45
`
`oxygen content in an efficient manner by passing the water
`through an electrolytic cell for only a selected number of
`times.
`
`50
`
`In a preferred embodiment, the pump 18 is variable, such
`that the volume of water is forced through the electrolytic
`cell 12 at a selected rate. Pump 18 is coupled to a timer 28,
`such that the water is forced through the cell for a selected
`period of time,
`the flow rate and time being selected to
`ensure that the volume of water passes through the electro-
`lytic cell the selected number of times.
`For example, the electrodes 20 of the cell 12 may each
`have a length of 6—12 inches, and a width of 1.5—2 inches,
`a current of 1—30 amperes being applied to the electrodes.
`Depending on the desired use of the treated water, a content
`of dissolved oxygen is selected. In a preferred embodiment,
`it is believed that many benefits may be achieved through the
`use of water having a dissolved oxygen content of 13—17
`
`55
`
`60
`
`6
`ppm. To ensure that the volume of water contains this level
`of dissolved oxygen, the volume of water is passed through
`the electrolytic cell 15—55 times. If the selected volume of
`water to be treated changes, the flow rate and/or time are
`adjusted accordingly,
`to ensure that the volume of water
`flows through the cell the selected number of times.
`In a preferred embodiment, an inner diameter of the
`tubing 11 is selected to ensure that the system will move the
`water at or above a selected flow rate. It will be understood
`
`that the size of the tubing will vary with the scale of the
`system; however, in a preferred embodiment, the tubing 11
`has a diameter of 0.5 inch. To further ensure that a desired
`flow rate is achieved, the tubing is configured to eliminate
`flow restrictions.
`
`A method and apparatus for increasing the dissolved
`oxygen content of a volume of water to a selected level have
`been shown and described. From the foregoing, it will be
`appreciated that although embodiments of the invention
`have been described herein for purposes of illustration,
`including specific examples, various modifications may be
`made without deviating from the spirit of the invention.
`Thus, the present invention is not limited to the embodi-
`ments described herein, but rather is defined by the claims
`which follow.
`What is claim is:
`
`1. Apparatus for increasing the dissolved oxygen content
`of a volume of water comprising:
`an electrolytic cell coupled to a source of current;
`a tank for holding a selected volume of water in fluid
`communication with the electrolytic cell
`a pump in fluid communication with the volume of water,
`the pump forcing the entire volume of water to flow
`through the electrolytic cell a selected number of times
`a timer circuit coupled to the pump for setting the length
`of time the pump is on, the on time of the pump being
`selected based on the tank volume to cause the water in
`
`the tank to circulate a selected number of times through
`the cell and stopping the circulation water after it has
`circulated the selected number of times.
`
`2. The apparatus according to claim 1 wherein the pump
`is variable such that the volume of water is forced to flow
`through the electrolytic cell at a selected rate.
`3. The apparatus according to claim 1, further comprising
`tubing provided between the pump, the electrolytic cell and
`the tank, an inner diameter of the tubing being selected to
`ensure a desired flow rate.
`
`4. The apparatus according to claim 3 wherein the diam-
`eter of the tubing is 0.5 inch.
`5. The apparatus according to claim 3 wherein the tubing
`is configured to provide an unrestricted flow path between
`the tank and the electrolytic cell.
`6. The apparatus according to claim 1, wherein the
`selected number of times is greater than nineteen (19).
`7. The apparatus according to claim 1, wherein the
`selected number of times is less than twenty-four (24).
`8. The apparatus according to claim 1, wherein the
`selected number of times is less than twenty (20).
`9. The apparatus according to claim 1, wherein the
`selected number of times is greater than fourteen (14) and
`less than twenty four (24).
`
`