US1767265A

US1767265A - Apparatus for electrical precipitation

Info

Publication number: US1767265A
Application number: US151496A
Authority: US
Inventors: Sykes Wilfred
Original assignee: NEBLETT ENGINEERING Co
Current assignee: NEBLETT ENGINEERING Co
Priority date: 1926-11-29
Filing date: 1926-11-29
Publication date: 1930-06-24
Anticipated expiration: 1947-06-24

Description

June 24, 1930. w. SYKES APPARATUS FOR ELECTRICAL PRECIPITATION 3 Sheets-Sheet 1 Filed Nov. 29, 1926 June 24, 1930. w. SYKES APPARATUS FOR ELECTRICAL PRECIPITATION Filed Nov. 29, 1926 3 Sheets-Sheet 2 p Ef /$1121 June 24, 1930. w. SYKES APPARATUS FOR ELECTRICAL PRECIPITATION Filed Nov. 29,'l926 5 Sheets-Sheet 5 Zfrecl Patented June 24, 1930 UNITED- STATES memes PATENT orrica I wmrnnn syxns, or omcaao, ILLINOIS, ASSIGNOR 'ro THE nnnm'rr nnofimnnclfie company, or CHICAGO, ILLINOIS, A oonrom'rron or ILLmoIs a APPARATUS FOR ELECTRICAL PRECIPITATION Application filed November 29, 1926. Serial No. 151,496.

My invention relates to apparatus for effecting the separation of solid particles from gaseous fluids, such for example as the separation of flue dust from the gaseous fluid dis- 6 charged into the stack from blastfurnaces, by the subjection of the gaseous fluid to an electrostatic field, or, in other words, to apparatus of the so-called electrical precipitation type.

In connection with one of the objects of my invention, it may be stated that the heavier the particles the more readily they may be precipitated lo the action of the electrostatic field, and the igher the velocity of the gaseous fluid, the greater the tendency of the sweeping of the particles from the collecting or precipitating, electrodes into the stream of gaseous fluid, and thus a velocity which would not be excessive as to the heavier 20 particles, would be excessive as to the lighter particles.

In apparatus, as hitherto provided, sofa'r.

as I am aware, no provision is made for compensating for this condition, which should tion of the course in which the fluid is subjected to the electrostatic-field, travels at a relatively high velocity during which travel.

7 the heavier of the solid particles are removed from the gaseous fluid; and throughout the remainder of the course travels at a relatively low velocity to permit of the effectual precipa "itatio'n of the lighter solid particles from the And herob'ct is to provide for the effecteconomicalfeonstruction and occupy the minispace. j

charge therefrom to occur over a large num-' Other objects are to provide an electrode of such form as to 'cause the electrical. disflier-of points at the face of the electrodeand whereby equalization of the pressure of the stream of gaseous fluid at opposite sides of theelcct'rode may be maintained substantially equalized; and other objects as will be manifest from the following description:

Referring to the accompanying drawings Figure 1 is an end view of apparatus ems bodying my invention. Figure 2 is a view in sectional elevation of the apparatus, the section being taken at the irregular line 2-2 on Fig. 3 and viewed in the direction of the arrows. Figure 3 is a view in vertical sectional elevation of the .apparatus viewing the latter from the right in Fig. 2, the section being taken at the irregular line 33 on Fig. 1 andviewed in the direction of the arrows. Figure 4 is a plan sectional view taken at vthe irregular line 4-4 on Fig.3 and viewed in the direction of the arrow. Figure 5 is an enlarged fragmentary cross sectional view of one of the similar negative, discharge electrodes of theapparatus; and Figure 6, a similar view of another detail of the ap aratus.

The apparatus shown and which, in practice, would be interposed in the course through which the gaseous fluid containing solid particles to be removed therefrom, flows, comprises a casing constructed of sheet metal to provide an upper chamber 11, and a lower chamber 12 the bottom of which latter is of hopper form, as' represented at 13, and contains an outlet 14: at its lower end-shown as controlled b a valve 15 mounted on a weighted lever 16 ulcrumed at 17 on the casing 10. The casin 10 is shown as 'containin a lurality of inlets 18 for the gaseous fiui to; be operated on, these inlets being located adjacent the upper end ofthe chamber/12;. the outlets vfor the cleaned gaseous fluid being represented at 19 and located in an end wall of; the casing, adjacent. the upper portion of the chamber 11. M

inlets 18,, though both the numberfof-inlets and the number of these fluesmay -bcyaried as 1 desired. Thetwo outermost 'flues-are formed by opposed side walls 21 of the casing which.

are arranged in parallel relation, and metal plates22 arranged parallel with the walla-21. The plates 22 extend the full length of the casing and from a point ad acent the upper portion of the chamber 12 to a point short of the bottom of the latter, as shown, the upper ends of the two outside fl'ues now being described, being closed by plates 23. The intermediate one of the flues 20 is formed of a pair of metal parallel plates 24 extending the full.length of the casing and reaching from a point adjacent the upper extremity of the chamber 12 to-a point short of the bottom thereof, the upper end of this flue being closed by a plate 25.

The fiues 20 thus extend downwardly through the casing and open into the bottom thereof, the opposed side walls of these fiues, in the operation of the apparatus, being positively electrically'charged and forming plate precipitators for the solid particles in the gaseous fluid passed therethrough.

The apparatus also comprises upwardly discharging fiues into the lower ends of which gaseous fluid discharged from the lower ends of the fiues 20, passes, and thence upwardly into the chamber 11, these fiues being represented at 26 and in accordance with one feature of my invention present a combined cross sectional area greater than the combined cross sectional area of the flues 20. In the arrangement shown each flue 26 is of F the same cross sectional area as that of each of discharge electrodes which, in the o eration of the apparatus, are negatively charged. The discharge electrodes in the fiues 20 are represented at 28, these electrodes being of general plate-like form preferably of the construction hereinafter described and suspended in these flues midway between the opposite side walls thereof and in spaced relation thereto, as by means of chains 29 connected with the upper edges of the electrodes 28 adjacent the ends thereof, and extending upwardly through openings in the plates closing the upper ends of these flues and through insulators 30 extending through these plates and supported thereon as shown, the upper ends of the chains 29 being connected with supporting cross members 31 seated on the insulators 30, intermediate ones of the cross members 31 being electrically connected together by a metal bar 32 which is connected with a conductor 33 extending upwardly through an insulator 34 mounted in the top of the casing 10, and, in practice, connected with the negative side of a high potential electrical circuit, the positive side of which would be grounded and thus in circuit with the precipitator electrodes described.

The flues 26 contain negative, discharge,

electrodes 35 preferably of the construction.

hereinafter described and supported to extend parallel with, and equidistantly from, the opposite walls of the fiues in which they are located, as by means of chains 36 connected with the cross members 31 and thus negatively charged in the operation of the apparatus, it being preferred that the lower edges of all of the negative electrodes extend substantially in the same plane and above the lower edges of the positive electrodes.

It may be here stated that the various intermediate precipitator electrodes are secured in place in the casing by any means suitable for maintaining them in the desired parallel relation. In the particular construction shown these intermediate electrodes are mounted at their lateral edges between angle irons 37 secured to the end walls of the casing, and between their ends engage at channel bars 38 thereon with spacer members 39.

It is preferred that the precipitator electrodes located between the electrodes 21, be each formed of two parallel plate members 40 (Fig. 6) connected together by a marginal frame represented at 41 and located between these plates and secured thereto in any desirable, way.

The negative, or discharge, electrodes, may be formed of sheetmetal, but preferably are formed as illustrated, namely, to provide those portions thereof which parallel adjacent positive electrodes, of interstitial form, for the dual purpose of providin for the electrical discharge'from the negative to the positive electrodes from a large number of points on the negative electrodes and the equalization of the gas pressure at opposite sides of the negative electrodes. Such form of negative electrode may be provided by.

forming it of sheets 42 of expanded metal which a e secured in parallel, spaced apart relation, by means of a marginal frame 43,

shown as formed of channel irons, the frame being located between the sheets 42 with the marginal edges of these sheets bent to lap the frame 43 as illustrated in Fig. 5 and in such position secured in any desired manner, as for example by welding them thereto.

The operation of the apparatus is as follows: The gaseous fluid from which the solid particles therein are to be separated, enters the casing 10 through the inlets 18 thence passing downwardly through the fiues 20, substantially equal distribution of the gas throughout these fiues being effected by the provision of deflectors 44, the fluid discharging from the lower ends of these fiues into the bottom of the chamber 12 and thence rising through the fiues 26 into the chamber 11 from static field for a which latter it discharges through the outlets The

electrodes

28 and 35 being negatively charged with the high potential current, the solid particles in the gaseous fluid travellingthrough the fines as stated are subjected to a strong electrostatic field whereby the solid particles become negatively charge and thus become attracted to the positive electrodes forming the walls of the fines, and become precipitated thereon.

In the passage of the gaseous fiuid through the down fines referred to, the heavier particles therein are either depos'ted on the sides of the precipitator electrodes or drop out of the gas stream when the direction of'flow of the latter changes by virtue of the provision of the upwardly extending outlet fines and the velocity of the gas stream becomes reduced because of the provision of the up flues as of larger efiective crosssectional area than the down flues. The gaseous from the chamber 12 upwardly through the up fines, at a reduced velocity, with the'result of efifecting the precipitation of the lighter particles upon the precipitator electrodes an thus the gaseous fluid discharges from the apparatus substantially free of sol cles, it being noted that by reason of the reduction of the velocity of the gas in the up flues the particles aresubjected tothe electrogreater length of time and likelihood of the sweeping of the particles from the precipitator electrodes, is practically eliminated.

It is desirable that means he provided in apparatus of this character, for subjecting the positive electrodes to a rapping action to dislodge the particles precipitated thereon, this being effected, in the particular construction shown, by providing, for with the positive electrodes, hammers 45 mounted on rock shafts 46 to extend between adjacent ones of the positive electrodes and alternately rap them in the oscillations of the shafts 46, these shafts being provided at their outer ends with arms 47 pivotally connected with an operating bar 48. The means the negative electrodes comprise hammers 49 secured on shafts 50 in id particooperation 7 While l have illustrated and described a particular embodiment of my invention, 1 0 not wish to be un limit it thereto as the same maybe variously modified and alteredwithout departing from the. spirit of my invention. a

What I claim as new, and desire to secure by Letters Patent, is:

In electrical precipitation apparatus, the combination of a casing containing a series of partitions forming flues certain of which are closed at their upper. ends and through which gaseous fluid introduced into the casing, descends, the others of said flues being open to receive, at their lower ends and direct upwardly therethrough, the fluid after passing through said first-referred-to flues, the

walls of said fiues forming positive electrodes, and negative electrodes located in said lines, the combined cross sectional area of those of the fines through wardly being greater than that of of said flues.

. v WILFRED SYKES.

ich the fluid passes up the others derstood as intending to 4 osition to be swung against the lower edges of the electrodes, the shafts 50 being provided with arms 51 pivotally connected with an actuating bar 52.

It will be understood from the foregoing that an apparatus constructed in accordance with my invention not only serves to very effectually clean the gaseous fluid of its contained solid particles, but may be economically constructed and is of very compact form, it being observed that the electrodes in the up fiues may be provided of greater length than those in the down fiues, with manifest advantage, without enlarging the apparatus.