US3873430A
Expired / Lapsed
US
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Method for automatic adjustment of anodes
Assignee: Olin Corp
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Filing: 1974-04-18
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Granted: 1975-03-25
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Expires: 1994-04-18
Abstract
Abstract An improved method for automatic adjustment of anodes in an electrolytic cell is described which utilizes the measurement of the rate of change in current density for a given unit of distance when a minor fraction of the anodes are lowered toward the liquid cathode. When the change in rate of current density exceeds a predetermined limit, movement of the minor fraction of anodes is stopped, and another minor fraction of anodes is adjusted.
Inventors
- 👤 Jr Richard W Ralston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:46
CPC Classifications
C; C25; C25B; C25B15/00; C25B15/04
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
181 words
IN AN ELECTROLYTIC CELL CONTAINING ADJUSTABLE ANODES, A LIQUID CATHODE AND AN AQUEOUS ELECTROLYTE WHEREIN A VOLTAGE IS APPLIED ACROSS SAID ANODES AND SAID CATHODE TO DEVELOP AN ELECTRIC CURRENT FROM SAID ANODES THROUGH SAID AQUEOUS ELECTROLYTE TO SAID CATHODE, THE IMPROVED METHOD FOR POSITIONING A MINOR FRACTION OF SAID ANODES AT AN OPTIMUM DISTANCE FROM SAID CATHODE WHICH COMPRISES A. POSITIONING A MINOR FRACTION OF SAID ANODES ABOVE SAID CATHODE AT A DISTANCE APART SO THAT WHEN SAID MINOR FRACTION OF ANODES IS MOVED IN EITHER DIRECTION AN INCREMENTAL DISTANCE, THERE IS A RELATIVELY SMALL CHANGE IN CURRENT PASSING THROUGH SAID MINOR FRACTION OF ANODES, B. MOVING SAID MINOR FRACTION OF ANODES IN THE DIRECTION OF SAID CATHODE AT A SUBSTANTIALLY CONSTANT RATE, C. MEASURING SAID CURRENT THROUGH SAID MINOR FRACTION OF ANODES AND CALCULATING THE CURRENT DENSITY PER UNIT OF DISTANCE AS SAID MINOR FRACTION OF ANODES MOVES TOWARD SAID CATHODE, AND D. DISCONTINUING MOVEMENT OF SAID MINOR FRACTION OF ANODES TOWARDS SAID CATHODE WHEN THE CHANGE IN SAID CURRENT DENSITY, PER UNIT OF DISTANCE REACHES A PREDETERMINED LIMIT.
Claim 2
Dependent Claim
181 words
IN AN ELECTROLYTIC CELL CONTAINING ADJUSTABLE ANODES, A LIQUID CATHODE AND AN AQUEOUS ELECTROLYTE WHEREIN A VOLTAGE IS APPLIED ACROSS SAID ANODES AND SAID CATHODE TO DEVELOP AN ELECTRIC CURRENT FROM SAID ANODES THROUGH SAID AQUEOUS ELECTROLYTE TO SAID CATHODE, THE IMPROVED METHOD FOR POSITIONING A MINOR FRACTION OF SAID ANODES AT AN OPTIMUM DISTANCE FROM SAID CATHODE WHICH COMPRISES A. POSITIONING A MINOR FRACTION OF SAID ANODES ABOVE SAID CATHODE AT A DISTANCE APART SO THAT WHEN SAID MINOR FRACTION OF ANODES IS MOVED IN EITHER DIRECTION AN INCREMENTAL DISTANCE, THERE IS A RELATIVELY SMALL CHANGE IN CURRENT PASSING THROUGH SAID MINOR FRACTION OF ANODES, B. MOVING SAID MINOR FRACTION OF ANODES IN THE DIRECTION OF SAID CATHODE AT A SUBSTANTIALLY CONSTANT RATE, C. MEASURING SAID CURRENT THROUGH SAID MINOR FRACTION OF ANODES AND CALCULATING THE CURRENT DENSITY PER UNIT OF DISTANCE AS SAID MINOR FRACTION OF ANODES MOVES TOWARD SAID CATHODE, AND D. DISCONTINUING MOVEMENT OF SAID MINOR FRACTION OF ANODES TOWARDS SAID CATHODE WHEN THE CHANGE IN SAID CURRENT DENSITY, PER UNIT OF DISTANCE REACHES A PREDETERMINED LIMIT.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said predetermined limit is within the range from about 2 and about 10 kiloamperes per square meter per millimeter.
Claim 4
Dependent Claim
8 words
D is the decomposition voltage of said electrolyte,
Claim 5
Dependent Claim
8 words
D is the decomposition voltage of said electrolyte,
Claim 6
Dependent Claim
100 words
wherein said adjusting comprises a. increasing the space between said minor fraction of anodes and said cathode by a distance of above about 3 millimeters, h. moving said minor fraction of anodes in the direction of said cathode at a substantially constant rate, i. measuring said current through said minor fraction of anodes and calculating the current density per unit of distance as said minor fraction of anodes moves toward said cathode, and j. discontinuing movement of said minor fraction of anodes towards said cathode when the change in said current density per unit of distance reaches a predetermined limit.
Claim 7
Dependent Claim
100 words
wherein said adjusting comprises a. increasing the space between said minor fraction of anodes and said cathode by a distance of above about 3 millimeters, h. moving said minor fraction of anodes in the direction of said cathode at a substantially constant rate, i. measuring said current through said minor fraction of anodes and calculating the current density per unit of distance as said minor fraction of anodes moves toward said cathode, and j. discontinuing movement of said minor fraction of anodes towards said cathode when the change in said current density per unit of distance reaches a predetermined limit.
Claim 8
Dependent Claim
25 words
The method of claim 2 wherein said predetermined limit is in the range from about 3 to about 5 kiloamperes per square meter per millimeter.
Claim 9
Dependent Claim
12 words
The method of claim 2 wherein said adjustable anodes are metal anodes.
Claim 10
Dependent Claim
98 words
M2 is the area in square meters of the cathode surface below said minor fraction of anodes, b. continuing operation of the cell for a predetermined period, c. measuring the voltage across said minor fraction of anodes, d. measuring the current to said minor fraction of anodes, e. calculating the voltage coefficient Vc according to said formula, f. comparing said Vc with said standard voltage coefficient S for said minor fraction of anodes, g. adjusting the space between said minor fraction of anodes and said cathode where the difference between Vc and S falls outside of k, where
Claim 11
Dependent Claim
98 words
M2 is the area in square meters of the cathode surface below said minor fraction of anodes, b. continuing operation of the cell for a predetermined period, c. measuring the voltage across said minor fraction of anodes, d. measuring the current to said minor fraction of anodes, e. calculating the voltage coefficient Vc according to said formula, f. comparing said Vc with said standard voltage coefficient S for said minor fraction of anodes, g. adjusting the space between said minor fraction of anodes and said cathode where the difference between Vc and S falls outside of k, where
Claim 12
Dependent Claim
12 words
The method of claim 2 wherein said adjustable anodes are graphite anodes.
Claim 13
Dependent Claim
29 words
The method of claim 4 wherein said minor fraction of anodes is in the range from about 2.5 to about 25 percent of the total anodes in the cell.
Claim 14
Dependent Claim
28 words
The method of claim 6 wherein said minor fraction of anodes is the range between about 5 and about 15 percent of the total anodes in the cell.
Claim 15
Dependent Claim
24 words
The method of claim 7 wherein all of the anodes in the cell are positioned above the optimum distance before adjusting said minor fraction.
Claim 16
Dependent Claim
32 words
The method of claim 7 wherein said minor fraction of anodes is moved in the direction of said cathode at the rate of between about 0.1 and about 1.0 millimeter per second.
Claim 17
Dependent Claim
69 words
The method of claim 9 wherein said rate of change in current density for said minor fraction of anodes is calculated by a digital computer which in response to electric signals, senses current and distance moved by said minor fraction of anodes, calculates the change in current density per unit of distance, and stops movement of said minor fraction of anodes when the current density exceeds said predetermined limit.
Claim 18
Dependent Claim
40 words
The method of claim 10 wherein said minor fraction of anodes is moved by anode supports having sprockets attached to the upper portion thereof, said sprockets being moved by a chain cooperating with said sprockets and a motor driven gear.
Claim 19
Dependent Claim
20 words
The method of claim 11 wherein said motor driven gear is energized by a motor controlled by said digital computer.
Claim 20
Dependent Claim
24 words
The process of claim 1 wherein said minor fractions of anodes is raised a predetermined height to improve long term operations of the cell.
Claim 21
Dependent Claim
20 words
The process of claim 13 wherein said predetermined height is in the range from about 0.5 to about 1.5 mm.
Claim 22
Dependent Claim
32 words
The Process of claim 1 wherein said improved method comprises a. calculating at start-up an original standard voltage coefficient S, for a minor fraction of said anodes in accordance with the formula:
Claim 23
Dependent Claim
46 words
The process of claim 15, after said discontinuing movement, wherein said improvement also comprises measuring the current to said minor fraction of anodes for a predetermined period, and raising said minor fraction of anodes when the current during the predetermined period increases beyond a predetermined limit.
Claim 24
Dependent Claim
66 words
The process of claim 16, after measuring current for said predetermined period, wherein said improvement also comprises comparing the maximum current measurement during said predetermined period with the current initially attained when said minor fraction of anodes was stopped, and raising said minor fraction of anodes when the difference between the initial current and the maximum current attained during said predetermined period exceeds a predetermined limit.
Claim 25
Dependent Claim
45 words
The process of claim 16, after measuring current for said predetermined period, wherein said improvement also comprises calculating the average difference of said current measurements obtained during said predetermined period and raising said minor fraction of anodes when said average difference exceeds a predetermined limit.
Claim 26
Dependent Claim
82 words
The process of claim 15, after said discontinuing movement, where in said improvement also comprises, a. measuring voltage and current to said minor fraction of anodes and calculating a new voltage coefficient Vc for the resulting new position, b. comparing said new voltage corefficient Vc with original standard voltage coefficient S, c. changing standard voltage coefficient S to said new voltage coefficient Vc, when the difference between said new voltage coefficient Vc and said original standard coefficient S exceeds a predetermined limit.
Claim 27
Dependent Claim
11 words
KA is the current to said minor fraction of anodes, and,
Claim 28
Dependent Claim
11 words
KA is the current to said minor fraction of anodes, and,
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |