US1912053A - Electrical precipitator - Google Patents

Description

'May 30. 1933- 1 C H. AjwlNTERMu-rE- 1391-?053l ELECTRICAL PREC IPITATOR Filed June 15,1931 2 Sheets-Sheet l May 30, 1933. H. A. WINTERMUTE 1,912,053

ELECTRICAL PREGIPITATOR Filed Jun l5. 1931 2 Sheets-Sheet 2 N|\v r.

f am.

" Patented May 30, 1933 UNITED STATES PATENT OFFICE HARRY A. WINTERMUTE, OF PLAINFIELD, NEW JERSEY, ASSIGNOB T0 RESEARCH COB.-

PORATION, 0F NEW YORK, N. Y.,

.a coRPonATIoN or NEW Yom:

ELECTRICAL rREcIrITA'roB Application led June 15,

This invention relates to electrical precipitators for the removal of suspended particles from gases and especially to that type of precipitator which is divided into a plurality of horizontal gas passages by extended vertical surfaces which function as collecting electrodes. Its scope may be further dened in that it relates in particular to electrical precipitators intended for the collection of dry comminuted material which requires baffles or pockets on the surfaces of the collecting electrodes to prevent creepage of the deposited material along these surfaces.

Objects of the present invention are to provide a simple and economical collector electrode assembly which possesses sufficient rigidity to remain properly alined in the precipitator, which presents transverse pockets or other interruptions at the collecting surface toprevent material that is not definitely held to the surface from moving along the electrode and reentering the gas stream, which does not offer a highresistance to the passage of gas through the precipitator, and which presents a satisfactory terminating surface for the electric field. A further object is to provide a collector electrode asy collected material which tends to adhere to the electrode and build up beyond a permissible depth. A further object is to provide an electrical precipitator in which collectin electrodes ofthe type stated and the discharge electrodes are so arranged as to result in distinct advantages overv previously used and/or suggested constructions. More specifically, an object is to provide a collector electrode assembly in which a plurality of channel members, preferably of identical form, are arranged with the flanges of adjaf cent channels projecting in opposite directions and with the channel webs arranged in two parallel planes.

These and other objects of the invention will be apparent from the following specification, when taken with the accompanying drawings, in which: p A

Fig. 1 is a plan view of a precipitator con- 1931. Serial No. 544,569.

structed according to the invention, with Va i Figs. 4, 5 and 6 are fragmentary side, plan and end views, respectively, of a portion of the collecting electrode,

Fig. 7 is a somewhat diagrammatic plan view showing arrangements of the electrodes in the precipitator, and

Figs. 8 and 9 are similar diagrammatic views of other forms of collectorelectrode structures embodying the invention.

In Figs. 1, 2 and 3, which illustrate the invention as embodied in one known form of precipitator, the reference numeral 1 identifies the casing of the precipitator, which casing is supported by uprights 2 and has an inlet Hue 3, an outlet flue 4, and hoppers 5 for' the collection of the material.

An insulator housing 6 on the top wall of the casing 1 houses a pair of insulators 7 supporting a cross member 8 to `which is electrically connected a conductor 9 which asses outof thel housing through an insu ating bushing 10 and is connected to a source (not shown) of high potential current, prefcompleted by a ground connection attached to the housing. Depending from the cross g member 8 is a vertical member 11 which ex-` tends through an opening in the top wall of the casing and carries a supporting frame 12 from which are suspended a plurality of discharge electrodes 13 arranged in rows eX- tending longitudinally of the chamber. A spacing frame 14 secured to the lower ends of the electrodes serves to maintain the electrodes in proper spaced relation.

The opening between the casing 1 and the housing 6v is closed by an annular insulator 15 of comparatively flexible, heat resisting, insulating material, such as asbestos cloth, which is'secured at its outer diameter to the top wall of the housing and at its inner diameter to the vertical member. The insulapath of the gas. Such an arrangement is employed where the gas passing through the pended material is insulating in character, thus the insulator is heated by the gas and l no condensation of suspended gaseous ma'- terial occurs. Where the gas which is treated is normally below the dew point and/or the suspended material is of a conducting nature, the insulator is located out of the gas stream so that the gas does not lreadlily encounter the insulator.

Extendingacross each end of the chamber isa pair of vvertically spaced supporting members 16 which carry two sets ofverticallyl alined collector electrodes 17 that extend t rough the casing 1 to subdivide the space within the casing into a plurality of relatively narrow gas passages. As shown in Fig. 1, each collector electrode is not flat but includes flat or plane sections which lie in two diierent vertical planes, thus giving the effect of a plate having flat corrugations that are relatively wide and shallow.

A lurality of rapping devices 18, which may vibrators operated by air pressure, steam or electrical means, are mounted on the casing 1 and include rods 19 lwhich extend through the casing and into engagement with the collector electrodes.

As shown in Figs. 4, 5 and 6tlie collector.

electrodes 17 are not formed by corrugating an elongated metal plate but are built up from a plurality of channel members which are secured to the reversely bent -members 20, 21; the ends of the upper member 20 being projected somewhat beyond those of the lower member 21 to engage the supporting members 16. `The webs 22 of the channel members lie in two spaced parallel lanes and the ilanges 23 of the channels pre erably do not contact with each other but, as shown in Fig. 46, en-

sections of the members 21, 22. The securing means, such as rivets 24, which fasten the channels to the members 20, 21 -pass through and the- 'tion of the disc arge electrodes 13 in sai .altapassagm it is noticed that the discharge l nce a is ap reciably less u' than discharge distance c. llhe' strongest precipitator is hot and dry and/or the susgage opposite faces of the short transverse l 19 pa through the'lower4 electric field will be, of course, from the discharge electrode 13a to the back of the channel web 22a to give a discharge distance portion of the gas passage.l Particles leaving this part of the passage, however, continue to lind themselves in a comparatively strong electric field when they pass between discharge electrode 13b and the open side of' the next channel 226.

The relative dimensions of the pockets formed by the channel members are important if the collector electrodes are to function at high efficiency and positively retain material which is swept out of the narrow portions of the gas passage and into the wider spaces where the open sides of the channels 226 oppose each other. While the optimum dimensions may vary somewhat with different installations, the ,channel depth should, in general, be at least one inch and preferably about two inches, that is, distanceici should exceedl the distance a by at least one inch.

The breadth b of the pockets is also important and, in general, it will 'be found -that a channel Width of between about 12 and 2A inches will give satisfactory results. The

spacing, d, of the discharge electrodes 13 should be at least equal to the minimum spacing a between thetwo sets of electrodes but ,the exact spacing for optimum results will depend upon the particular installation and the gases to be treated.

The dimensions dictated by the'electrical from a requirements are quite satis actory of about four feet in length may be of relatively light weight as the flanges 23 will reinforce the webs 22, thus stiiness even though the 'channels-are formed of relatively thin metal sheets.

As shown in Fi 8, partially closed ockets may be provided at the edges of the c annels away from the stream by flanges 26 which project m the webs 22' ssn' iool

lmechanical standpoint. Channel members providing suicient llt) and across a part of the trailing-edge of the preceding pocket. I

A similar arrangement is shown in Fig. 9 in which one flange 27 of each plate 1s bent over to provide a short section parallel to the web 28 of the channel. To secure a relatively uniform iield throu hout the gas passage, tubes or bars 29 are p aced across the opening of the channel to provide a terminating surface for the electric field in this re on.'

While the electric field terminates to a arge extent on these bars, the moving material which leaves the back of an adjacent channel -member can pass around .the bars to enter the pocket behind them. y

The invention provides a simple,l 1ght and relatively inexpensive construction Yin which lll a plurality of rectangular shaped pockets are provided for trapping material that tends to slide along the face of the collecting electrodes, the= material being retained in the y pockets until, either by its own weight or due to rapping, it drops down the surface of the pocket and into the collecting hoppers. There is but little tendency for the dust to sneak out of the rectangular shaped pockets and this tendency may be reduced by employing the types of channel shown in Figs. 8 and 9. The resistance to gas flow is not materially increased by the construction, particularly when the pockets are not close together and the changes in gas velocity are neither abrupt nor frequent.

Itis to be understood that the invention is not limited to the particularrarrangements which have been described as various changes may be made in the parts and in their relative size, shape and relationship without departing from the spirit of the invention as set forth in the following claims.

I claim:

1. In an electrical precipitator, the combination with a casing defining a gas chamber, of a plurality of collecting electrodes disposed in spaced, parallel alinementto define a plurality of gas passages in said chamber, and discharge electrodes in said passages, each of said collecting electrodes comprising a plurality of members having longitudinal stiifening flanges, said members being dis-- posed in alinement with their anges adjacent one another and with the similar faces of adjacent members facing in opposite directions.

2. The invention as Yset forth in claim 1, wherein the flanged members of the two collecting electrodes which cooperate to define a gas passage are transversely alined, and the concave sides of ianged members of one electrode are opposite the concave sides of the ianged members of the other electrode.

3. In an electrical precipitator, a collector electrode comprising a pair of reversel)7 bent members having relatively long, flat sides arranged alternately in two parallel planes and joined by short transverse sections, and channel members arranged with ends of the Webs thereof engaging the flat sides of side members and with the webs thereof engaging lthe said short transverse sections, means passed through channel members and said reversely bent members to connect said members to each other. p

4. The invention as set forth in claim 3, wherein the opposedlanges of adjacent channel members engage opposite sides of the transverse sections of said.' reversely -bent members, thereby to space adjacent flanges from each other.

5. The invention as set forth in claim 3, wherein said connecting means are located only at the flanges of said h'annel members.

6. In an electricall precipitator, the combination with a gas chamber, and discharge electrodes therein, of a collector electrode comprising a supporting member and vertically disposed members carried by said su porting member to provide a. substantial y continuous collector surface extending in theV direction of gas iiow through said chamber, one of said vertically disposed members comprising a channel having web and flange elements, the web of said channel being offset from the plane of the adjacent portions of the collector electrode to form a vertically disposed pocket.

7. The invention as set forth in claim 6, in combination with means extending parallel to and spaced from said channel web to partially close said pocket.

8. The invention as set forth in cla im 6, in combination with spaced conducting means extending across said pocket and in the plane of the said l'adjacent portions of the collector elect-rode.

9. In an electrical precipitator, the combination with a casing providing a gas chamber, of a plurality of collector electrodes de- 'fining gas passages in said chamber and discharge electrodes in said gas passage, each of said collecting electrodes comprising a plurality of alined channel members and means partially closing the channels.

10. The invention as set forth in claim 9, wherein said means comprises a projecting portion on each of said channel members portion on each of said channel members' extending from a liange thereof and parallel to the web of the channel member.

12. The invention as set forth in claim 9,

wherein said means includes a plurality of jecting from the web of each of Vsaid channel members and arranged to overlie the channel of an adjacent channel member.

14. An electrode for electrical precipita,- tors comprising a plurality of vertically disposed channel members arranged side by sidel to constitute a substantially continuous surface, and means for connecting said channel members includin members secured to the ends only of said c annel members, and lyingflat against the surfaces of at least some of said channel members.

15. In an electrical precipitator, the com vbination with collector electrodes defining a gas passage and each having portions of the collecting surface arranged in different parallel planes extending along said gas passage, of a series of discharge electrodes in irs` said gas passage and cooperating with said collector electrode, at least one discharge i electrode being positioned opposite each of said portions of said collecting surface.

`16. In an electrical precipitator, a pair of collector electrodes having substantially continuous opposed surfaces defining a gas passage, the opposed surfaces of said electrodes being symmetrically disposed at opposite sides of the medial plane of said passage and including portions l ing at different distances from said medial plane, whereby the gas passage includes zones whose transverse width is greater than that of other zones, and discharge electrodes in said gas passage and between those opposed surfaces of said collector electrodes which define a narrow zone.

17 The invention as set forth in claim 16,

in combination with discharge electrodes arranged in said gas passage at the wider zones thereof. 18. In an electrical precipitator, in combination, a collecting electrode comprising a plurality of composite collecting elements disposed substantlally parallel and defining a gas passage, each of said composite elements including a plurality of rectilineally grooved members extending transversely to the direction of gas flow in the passage, and a plurality ofdischarge electrodes in said passage, at least one of such dischar e electrodes in said passage being dispose opposite each of said grooved members.

19. In an electrical precipitator, a collector electrode comprising a-supporting member, and a plurality of channel members secured to said supporting member with the open sides of adjacent channels faced in opposite directions, the lian es of each channel member lyin the respective adJacent channel member, and

being spaced from the anges thereof.

In testimony whereof, I aix my signature.

HARRY A. WINTERMUTE.

within t e open space of

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