US3686829A

US3686829A - Double wire discharge electrode assembly

Info

Publication number: US3686829A
Application number: US87401A
Authority: US
Inventors: James F Stocker
Original assignee: Kennecott Copper Corp
Current assignee: Kennecott Utah Copper LLC; Kennecott Corp
Priority date: 1970-11-06
Filing date: 1970-11-06
Publication date: 1972-08-29
Anticipated expiration: 1989-08-29

Abstract

A discharge electrode assembly for use in an electrical gas precipitator has a pair of contiguous elongate wires extending between mounting means attached at one end thereof for suspending the electrode vertically within the precipitator and a pair of concentric cylindrical weights attached respectively to the other ends of the wires. Sufficient space is provided between the inner and the outer weights to permit precipitates to fall through to the bottom of the precipitator. Both weights preferably have enclosed, dome-shaped tops with respective lateral slots extending from one outer edge to the center of the tops. The slots accommodate enlarged extensions on the wire ends and permit the weights to be easily secured on the wires. The inner weight can be rotated within the outer weight to lock the wires within the slots so that accidental disconnection cannot take place during use. The wires are individually tensioned by the weights, and can continuously move longitudinally and rotationally with respect to each other to remove any adhering precipitates.

Description

United States Patent Stocker [4 Aug. 29, 1972 [54] DOUBLE WIRE DISCHARGE ELECTRODE ASSEMBLY [72] Inventor: James F. Stacker, Kearny, Ariz.

[73] Assignee: Kenneeott New York, N.Y.

[22] Filed: Nov. 6, 1970 [21] Appl. No.1 87,401

[52] US. Cl. ..55/l47, 55/148, 55/149, 55/151 [51] Int. Cl "B038 3/41 [58] Field of Search ..55/l46, 147,148, 149, 150, 55/151, 152,153

[ References Cited UNITED STATES PATENTS 2,959,246 11/ 1960 Phyl et a1 ..55/ 147 FOREIGN PATENTS OR APPLICATIONS 341,229 9/1921 Germany ..55/ 150 Primary Examiner-Dennis E. Talbert, Jr.

Attorney-John L. Sniado, Mallinckrodt & Cornaby and Philip A. Mallinckrodt ABSTRACT A discharge electrode assembly for use in an electrical gas precipitator has a pair of contiguous elongate wires extending between mounting means attached at one end thereof for suspending the electrode vertically within the precipitator and a pair of concentric cylindrical weights attached respectively to the other ends of the wires. Sufficient space is provided between the inner and the outer weights to permit precipitates to fall through to the bottom of the precipitator. Both weights preferably have enclosed, dome-shaped tops with respective lateral slots extending from one outer edge to the center of the tops. The slots accommodate enlarged extensions on the wire ends and permit the weights to be easily secured on the wires. The inner weight can be rotated within the outer weight to lock the wires within the slots so that accidental disconnection cannot take place during use. The wires are individually tensioned by the weights, and can continuously move longitudinally and rotationally with respect to each other to remove any adhering precipitates.

10 Claims, 8 Drawing Figures PATENTEU 2 9 SHEET 1 0F 2 INVENTOR.

E. STOCKER JAMES BY Al ATTORNEY DOUBLE WIRE DISCHARGE ELECTRODE ASSEMBLY BACKGROUND OF THE INVENTION FIELD This invention relates to electrical precipitators for removing particulate matter from gas streams, and more particularly to an improved discharge electrode assembly having self-cleaning capabilities.

STATE OF THE ART Electrical precipitators have long been employed to extract precipitates and other foreign particulate matter such as dust from moving gas streams. Elec-' trodes in the precipitator create an electrical charge which attracts particulate matter from the gas and causes it to settle out of the stream. The electrodes are customarily shaken or rapped periodically to remove precipitates which have accumulated thereon. The single wire discharge electrodes in common use today form hard shells of precipitates around the electrodes which are removable only with great difficulty, if at all, by the conventional vibratory or rapping methods. The continuous presence and accumulation of precipitates on the electrodes interferes with the electrical conductivity and causes decreased efiiciency. Although attempts have been made heretofore to employ a double wire electrode as a means of removing adhering precipitates through abrasion between the wires, the attached weight systems have Proved unacceptable. As precipitates are removed from the double wires, they fall onto the weight systems below and into the small cracks between the individual weights. This causes the weights to adhere together to effectively eliminate individual tension on the wires, prevent relative motion of the wires, and add increased undesirable weight to the electrode.

OBJECTIVES It was an objective in the development of this invention to provide a discharge electrode assembly which would be self-cleaning and would not trap precipitates as they fall from the electrode wires. It was an additional objective to provide electrode weights which are easily detached from the electrode wires for rapid replacement of broken wires.

SUMMARY OF THE INVENTION In accordance with the invention, a discharge electrode for use in an electrical precipitator includes a pair of elongate electrode wires adapted to be suspended vertically in contiguous relationship with each other within the precipitator. Mounting means for suspending the respective wires is attached to one end of the wires. At the other end of the wires a pair of cylindrical weights are arranged in concentric relationship with each other and are attached respectively to the wire ends. The tops of the weights preferably are enclosed, and have lateral slots extending along each top from the outer edge to the center thereof. The slots accommodate enlarged portions of the wire ends, so that the weights can be hung from the respective wires to provide individual tensioning of the wires. The concentric weights have sufficient space between the outer walls of the inner weight and the inner walls of the outer weight to permit precipitates from the wires to fall through the weights to the bottom of the precipitator, thereby preventing accumulation of precipitates in the weights and the resulting binding of the weights together. The natural motion of the individually tensioned wires relative to each other, in both longitudinal and rotational directions, cause any accumulated precipitates to be rubbed off the wires and to fall through the weights without hindering the functioning of the weights. The enlarged ends of the wires are adapted to be easily inserted and removed from the slots in the tops of the weights for convenient replacement of broken wires. As an additional safety feature,

the inner concentric weight can be rotated within the outer weight to effectively lock the wires within the slots, thereby preventing accidental disconnection of the weights during use. Conventional stabilizing means, for example in the form of a laterally extending stabilizer bar within the precipitator, can be employed to prevent the electrodes from swaying excessively and coming into contact with each other. If a stabilizer bar is utilized, both concentric electrode weights have lateral slots extending from the bottom of the weights upwardly toward the center thereof to accommodate the stabilizer bar.

The electrical precipitator for use with the discharge electrodes can be of the standard design, having a housing with means for introducing gases to be cleaned and for withdrawing the clean gases. A plurality of conventional plate collecting electrodes are customarily disposed vertically within the housing in spaced lateral relationship with each other, with a plurality of discharge electrodes in spaced arrangement with each other disposed in single rows between adjacent pairs of collector plates. A suitable power source is connected to the electrodes to provide an electrical charge.

THE DRAWINGS The best mode presently contemplated of carrying out the invention is illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevational section of an electrical precipitator showing a row of discharge electrodes;

FIG. 2, an end elevational section taken along the line 2-2 of FIG. 1, showing the arrangement of alternating discharge and collecting electrodes;

FIG. 3, a top plan section taken along line 3-3 of FIG. 1, showing the arrangement of discharge and collecting electrodes within the precipitator;

FIG. 4, an elevational section of a discharge electrode taken along line 4-4 of FIG. 1, showing the concentric weights and means for attaching the electrode to the precipitator;

FIG. 5 an elevational section taken along line 5-5 of FIG. 2, showing another view of the relationship between the weights and the electrode wires;

FIG. 6, a top plan section taken along line 6-6 of FIG. 5 illustrating the attachment of the pair of electrode wires to a rod for mounting the electrode within the precipitator;

FIG. 7, a top plan section taken along line 7-7 of FIG. 5 showing the arrangement of the concentric weights and the location of the electrode wires; and

FIG. 8, a top plan section taken along line 8-8 of FIG. 5 showing another view of the concentric weight arrangement.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS FIGS. 1, 2, and 3 illustrate a conventional electrical precipitator employing the improved discharge electrode assembly of the invention. The precipitator includes a housing enclosing the precipitation electrodes. Housing 10 is preferably air-tight to prevent the particulate matter and gases from escaping. The means for introducing particulate-bearing gases in this embodiment comprises a flue 11 located at one side of housing 10 through which the gas stream enters the lower portion of the precipitator. A clean gas exhaust flue 12 is provided near the top of housing 10 on the opposite side to remove the gas following precipitation of the undesirable particulate matter. When the precipitator is in use, the particulate matter falls to the bottom of housing 10, preferably into a bin or hopper 13 for periodical removal. Collecting electrodes 14 of the customary plate type are secured by means of lateral support brackets 14a, 14b, in vertical arrangement within housing 10 and are laterally spaced in parallel relationship with each other. A high tension frame 15 is disposed in the upper portion of housing 10 and comprises a plurality of laterally extending elongate support members 16 disposed above and intermediate adjacent pairs of collecting electrodes 14. Support members 16 are attached to a central lateral support member 17 extending perpendicularly across the tops of support members 16. High tension frame 15 is secured within housing 10 by a vertical bar 18 extending downwardly from an electrical insulator 19 disposed on top of housing 10. Insulator 19 is connected to an appropriate power source (not shown) for supplying electrical energy to the discharge electrode assemblies 20. Electrode assemblies 20 hang vertically suspended in rows from support members 16 intermediate adjacent pairs of collecting electrodes 15, and are arranged in spaced relationship to each other along support members 16. The electrodes are preferably detachably mounted in small slots 21 in support members 16.

The structure of discharge electrode assembly 20 is illustrated in detail in FIGS. 4, 5, 6, 7, and 8. The assembly has a pair of

elongate wires

22, 23 which are fixedly attached at their upper ends by appropriate means to the lower end of the electrode mounting means. In this embodiment the mounting means comprises an elongate rod 24 having a mounting bracket 25 fixedly attached to its lower end. Mounting bracket 25 has sufficient diameter to accommodate both

wires

22, 23 in a cooperating receptacle disposed in the bottom thereof. The wires can be swedged into place or secured by some other appropriate means. At the upper end of rod 24 an enlarged holding member 26 is fixedly attached thereto. Holding member 26 can be an integral part of rod 24, if desired, and tits cooperatively into the slots 21 arranged along support members 16 in the precipitator. Electrodes 20 are thereby suspended from members 16 when in use.

At the lower ends of

electrode wires

22, 23, each wire has an enlarged dowel 27, 28 fixedly attached thereto. The dowel is preferably larger in diameter than the wire. Alternatively, dowels 27, 28 may be formed integrally as enlarged portions of the wire ends. Dowels 27, 28 function as the support means for the pair of

weights

29, 30 which hang suspended from the respective electrode wires to effect individual tensioning of the wires.

Weights

29, 30 comprise a pair of cylindrical weights with

inner weights

29, 30 are dome-shaped to prevent precipitates from accumulating on top of the weights. Other similar configurations for the tops are also employable, such as conical or frusto-conical shapes. The top of each

weight

29, 30 has an aperture or

lateral slot

31, 32, extending from the outer edge of the weight to at least the center thereof.

Slots

31, 32 are adapted to accommodate dowels 27, 28 and have inwardly extending lips 33, 33a at the upper edges of the slots, so that dowels 27, 28 can rest within

slots

31, 32, and beneath

lips

33, 34, thereby supporting

weights

29, 30. It is important that sufficient space be provided between the enclosed tops of the weights so that dowel 27 has sufficient room to be accommodated within slot 32. In this illustrated embodiment inner weight 29 can be disposed within concentric outer weight 30 in such a manner that

slots

31, 32 are in alignment with each other to permit dowels 27, 28 to be inserted therein with

wires

22, 23 extending upwardly from the weights. Inner weight 29 can be rotated, for example l, within outer weight 30 to effectively secure or lock the dowels within the slots. As illustrated in FIGS. 5 and 7, wire 23 attached to inner weight 29 blocks the slot 32 in outer weight 30 to prevent wire 22 and dowel 27 from accidentally disengaging from slot 32.

Sufiicient space 34 is provided between inner weight 29 and outer weight 30 to permit particulate matter falling from the electrode wires to pass through the weights to the bottom of the precipitator. As an additional feature to enhance the passage of precipitates through the weights, inner weight 29 has inwardly tapered walls 35 to provide more space 34 near the bottom of the weights than near the top. It should be noted that space 34 should be large enough to provide for the passage of precipitates and also to permit relative movement between the two

electrode wires

22, 23 both longitudinally and rotationally, but should not be so large that the contiguous electrodes wires can separate from each other creating a corona discharge, spit arcing, or other electrical malfunctions.

As a means of stabilizing the electrodes, a plurality of stabilizing bars 36 extend laterally across the lower portion of the precipitator housing 10 and fit into cooperating slots or aperture 37 extending upwardly from the bottom of weights 28. Stabilizer bars 36 permit adequate vertical and rotational motion of the wires, but prevent undesirable contact between electrodes caused by excessive lateral motion of the weights.

Whereas this invention is illustrated and described herein with respect to certain preferred forms thereof, it is to be understood that many variations are possible without departing from the inventive concepts particu-. larly pointed out in the claims.

I claim:

1. A discharge electrode for use in an electrical precipitator for removing precipitates from gases, comprising:

a pair of contiguous, elongate wires;

mounting means at one end of the wires for attaching the wires to the precipitator;

a pair of concentric, cylindrical weights attached respectively to the other ends of the pair of wires,

endthereoftothepairofwiresandha 7 said weights having sufficient space between the I innerandoutercylinderstopermitprecipitatesto passtherethroughandtoperrnitthecontiguous wires to move longitudinally and rotationally with reapecttoeachother. ltAdischargeelectrodeassetforthinclaiml, wherein the inner concentric weight is tapered inwardlyfromtheupperendtothelowerendthereofto provide morespacebetweenthepairofweightsatthe lower and than at the upper end.

3.Adischargeclectrodeasaetforthinclaiml, wherein the concentric weights have respective lateral slots extending upwardly from the lower ends of the weights, said slots being adapted to accommodate a lateral stabilin'ng bar disposed within the precipitator for preventing lateral movement of the discharge electrodes with respect to each other.

4.Adischargeelectrodeassetfonhinclaim l. whereintherneansforattachingthewireatothe precipitator comprises an elongate rod attached at one ving an enlarged head at the other end adapted to fit into receptacles within the precipitator.

5. A discharge electrode as set forth in claim I,

wherein the concentric weights are detachably mounted on the electrode wires.

6. A discharge electrode as set forth in claim 5, wherein the wires have enlarged lower ends, and the cylindrical weights have closed tops and respective lateral slots extending from one outer edge of each top tothecenterthereof.saidslotsbeingadaptedtoaccommodate theenlarged endsofthe wires for mounting the weights on the wires.

'7.Ad'uchargeelectrodeassetforthinclaim. whereintheinnerconcentric weightisrotatahlewithin theouterweighttopermittheelectrodewirestobe secured within the lateral slots.

8.Atleastonedischargeel ectrodeassetforthin claim 1, in combination with an electrical precipitator W8 a precipitator housing adapted to collect precipitates at the bottom thereof;

at least one collector electrode disposed vertically within the housing in spaced relation with the discharge electrode;

means for introducing gases containing precipitates into the housing and for withdrawing purified gases therefrom; and

mean for introducing an electrical current into the precipitator.

9. A combination as set forth in claim 8, including means for preventing lateral movement of the electrodes.

10. A combination as set forth in claim 8. including a laterally extending elongate bar disposed in the upper portion of the housing said bar having spaced receptacles therein for receiving the mounting means on the discharge electrodes.

" UNITED STATES PATENT OFFICE.

569 CERTIFICATE OF CORRECTION Patent No. 3,686,829 Dated gust 29, 1972 Invent-(5) James F. Stocker It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

The middle initial of the inventor should be E. instead of "F. I

as it appears. Column 4, line 3, the following should be inserted between "inner" and "weights":

weight 29 disposed concentrically within outer weight 30. The tops of both Column 4, line 13, the reference number "34" should be 33a Signed and sealed this 23rd day of January 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesti-ng Officer Commissioner of Patents

Claims

1. A discharge electrode for use in an electrical precipitator for removing precipitates from gases, comprising: a pair of contiguous, elongate wires; mounting means at one end of the wires for attaching the wires to the precipitator; a pair of concentric, cylindrical weights attached respectively to the other ends of the pair of wires, said weights having sufficient space between the inner and outer cylinders to permit precipitates to pass therethrough and to permit the contiguous wires to move longitudinally and rotationally with respect to each other.

2. A discharge electrode as set forth in claim 1, wherein the inner concentric weight is tapered inwardly from the upper end to the lower end thereof to provide more space between the pair of weights at the lower end than at the upper end.

3. A discharge electrode as set forth in claim 1, wherein the concentric weights have respective lateral slots extending upwardly from the lower ends of the weights, said slots being adapted to accommodate a lateral stabilizing bar disposed within the precipitator for preventing lateral movement of the discharge electrodes with respect to each other.

4. A discharge electrode as set forth in claim 1, wherein the means for attaching the wires to the precipitator comprises an elongate rod attached at one end thereof to the pair of wires and having an enlarged head at the other end adapted to fit into receptacles within the precipitator.

5. A discharge electrode as set forth in claim 1, wherein the concentric weights are detachably mounted on the electrode wires.

6. A discharge electrode as set forth in claim 5, wherein the wires have enlarged lower ends, and the cylindrical weights have closed tops and respective lateral slots extending from one outer edge of each top to the center thereof, said slots being adapted To accommodate the enlarged ends of the wires for mounting the weights on the wires.

7. A discharge electrode as set forth in claim 6, wherein the inner concentric weight is rotatable within the outer weight to permit the electrode wires to be secured within the lateral slots.

8. At least one discharge electrode as set forth in claim 1, in combination with an electrical precipitator comprising: a precipitator housing adapted to collect precipitates at the bottom thereof; at least one collector electrode disposed vertically within the housing in spaced relation with the discharge electrode; means for introducing gases containing precipitates into the housing and for withdrawing purified gases therefrom; and means for introducing an electrical current into the precipitator.

9. A combination as set forth in claim 8, including stabilizing means for preventing lateral movement of the discharge electrodes.

10. A combination as set forth in claim 8, including a laterally extending elongate bar disposed in the upper portion of the housing, said bar having spaced receptacles therein for receiving the mounting means on the discharge electrodes.