FR2586942A1 - IMPROVEMENTS IN OR RELATING TO ELECTROSTATIC PRECIPITATION - Google Patents

Abstract

THE ELECTROSTATIC FILTER INCLUDES A COLLECTOR ELECTRODE SUSPENDED FROM A SUPPORT BAR LOCATED ON THE UPPER EDGE OF THE COLLECTOR ELECTRODE AND MEANS FOR TRANSMITTING SHOCKING SHOCK TO THE COLLECTOR ELECTRODE. THE COLLECTOR ELECTRODE12 IS ELASTICALLY SUSPENDED FROM THE SUPPORT BAR140 AND SHOCKING SHAKES ARE TRANSMITTED DIRECTLY TO THE COLLECTOR ELECTRODE WHERE IT IS ELASTICALLY SUSPENDED.

Description

I Improvements to electrostatic precipitation or

pertaining to it.

  This invention relates to improvements made

  electrostatic precipitation or related to it

  this. An electrostatic filter for electrostatic precipitation of dust or the like contained in gases

  includes discharge electrodes and collection electrodes

  grounded; the discharge electrodes are charged at a high potential to produce an electric field to precipitate the dust. The evacuation of dust housed on the collecting electrodes sometimes presents a problem and a shaking device is generally provided to produce shaking shakes

  to dislodge dust.

  It is known for example to maintain a collecting electrode

  using a bar above it, fixed so

  re elastic inside the filter housing and trans-

  shake the collector electrode

  through this bar; see for example GB-

  2047576 (Lodge-Cottrell Limited); however, it has been discovered that this arrangement apparently causes dissipation of the shaking energy in the barre. It is an object of the present invention to provide a system

  improved collector electrode for electrostatic filter.

  The invention provides a collector electrode assembly or system for an electrostatic filter comprising a collector electrode resiliently suspended from

  a support bar located on the upper edge of the elect

  collector trode, and means for transmitting jolts

  its shaking directly to the collecting electrode,

  where it hangs elastically.

  The invention also provides a system in which the elect

  collector trode comprises a generally flat panel part and a plurality of sections of profiles directed downwards, each of these profiles being situated on both sides of the flat panel part, and in which the

  means for transmitting shaking shakes comprising

  at least one shaking anvil which is arranged so that the shaking jerks applied to the anvil are transmitted directly to one of these profile parts, said profile part being aligned

with the anvil.

  Means for transmitting shaking may include

  a plurality of symmetrically spaced shaking anvils

  along the upper edge of the collecting electrode.

  Each shaking anvil is for example aligned with a section of the electrode profile and there can be two shaking anvils per electrode aligned with

  the sections of profiles at the outer ends of the elect

  collecting trode; or the two shaking anvils

  can be aligned with the intermediate profile parts

symmetrically spaced diaries.

  The invention also relates to a compressed electrostatic filter.

  providing a plurality of collector electrode systems

according to the invention.

  Other characteristics and advantages of the invention appear

  will be examined on examination of the detailed description below

  and attached drawings of the conforming electrostatic filter

  to the invention. This description is given only for

  example and in no way limit the scope

of the invention.

  In the accompanying drawings: - Figure 1 is a schematic side view of the electrostatic filter according to the invention;

  - Figure 2 is a horizontal section of the electrostatic filter

tick according to the invention;

  - Figure 3 is a longitudinal section of the electrical system

  collecting rod of the electrostatic filter; - Figure 4 is a perspective view of certain parts of the electrostatic filter; and - Figure 5 shows another embodiment of the

Figure 3 system.

  The electrostatic filter in the embodiment according to the invention is of the single-stage type and comprises (FIG. 1) a housing 2, a plurality of spaced apart collecting electrodes 12 (only one of them is shown in FIG. 1) , held in the housing 2, and a plurality of discharge electrodes 14 also held in the

  box 2 and located in the spaces provided by the elect

collecting trodes (cf. figure 2).

  The collecting electrodes 12 are similar to those

  described in document GB-1 157 602 (Lodge-CottreJ Limi-

  ted). The discharge electrodes 14 are for example produced substantially as described in GB-2,061,772 (Lodge-Cottrell Limited). The housing 2 comprises a gas inlet 3 and a gas exhaust 5, between which the dust-laden gas passes in the direction of the arrows X. The housing has a cover 7 and a lower outlet 9 to collect the precipitated dust. The filter also includes means for producing a high potential at the electrodes

discharge 14.

  When the filter is operating, the collecting electrodes 12 are grounded and the discharge electrodes are charged at a high potential; it follows that the dust is precipitated and extracted from the gas and is deposited on the collecting electrodes 12; certain amounts of dust are also deposited on the electrodes of

discharge 14.

  The filter comprises a shaking device 16 capable of producing shaking jolts in order to dislodge the dust deposited on the collecting electrodes 12

  and also includes a shaking apparatus 18 of confi-

  similar guration in order to dislodge the deposited dust

  on the discharge electrodes 14.

  The discharge electrodes 14 are generally arranged

  in planar rows, parallel to the direction of flow-

  gas, the rows alternating with the collecting electrodes 12. Each row of discharge electrodes

  14 is fixed to the upper and lower horizontal bars

superior 20 and 21.

  The bars 20 are held on the cover 7 by structures

  support 22 (only two of them are shown

  tees). Each structure comprises an elongated vertical tube 24, which is supported by an insulating assembly 26 mounted on the cover 7. The tube 24 passes through the cover 7 downwards and the lower end of the tube 24 is fixed to one

  of the two bars 28 perpendicular to the direction of flow

  gas, the bars 20 being fixed to the latter.

  For further details concerning the mounting of the discharge electrodes 14 in the housing 2, reference will be made to GB-2-047 576. The apparatus for discharging the discharge electrodes 18 is of the known type and will not be describes

in more detail below.

  Each collector electrode 12 (FIG. 2) comprises a plurality of adjacent coplanar panels 34, the edges of which are assembled using sections of vertical sections 36 on the two sides of the panels 34, the section having an opening in the opposite direction to

  that of the gas flow. Each part of the profile

  36 has ends 38 which are turned towards

  inside the side of the electrodes 34. Similar profiles

  ble 37 are provided on the opposite ends of the elect

  collecting trode 12. While the filter is operating,

  dust collects in particular in the profiles.

  Each collecting electrode 12 is suspended in an elastic manner on a horizontal upper bar 140 (FIGS. 1, 3 and 4) of hollow rectangular section, generally placed in the same plane as the electrode 12 which it supports,

  and is located along the upper edge of the latter.

  The ends of the bar 140 are rigidly fixed

  in the housing using two horizontal bars

  versals 42 (FIGS. 1 and 4), themselves supported on ledges 44 of box 2 and perpendicular to the direction of gas flow. The collecting electrode 12 is also fixed to a lower horizontal bar 141.

  Each part of the outer profile 37 of the collecting electrode

  trice 12 is resiliently mounted on the bar 140 using a coil spring 142; and a shaking anvil 144 of circular section above the bar 140, of the same axis as the spring 142, is arranged so that the shaking jerks can be transmitted directly to the profile part 37, independently of the bar 140, the profile part 37 being aligned with the anvil and the spring 142 acting between the bar 140 and the anvil 144. The intermediate profile parts

  36 are rigidly fixed to the bar 140 in a known manner.

  It will be noticed that this does not decrease in a way

  substantial elastic suspension of the collecting electrode

  trice because the bar has a certain flexibility.

  The intermediate parts of the profiles can be equally

  ment, in another embodiment, resiliently suspended from the bar 140 in the same way as the sections 37, but the arrangement is such that only the sections of sections 37 have anvils of shaking associated with them. The sections of sections 36 and 37 are also rigidly fixed to the bar-l41, which is itself suspended freely in the housing between slides (not shown) which limit movement

swaying.

  Each profile part 37 is held firmly on a part forming an upward extension between internal and external clamping pieces 146, 148 by means of bolts 150. The internal clamping piece 146 can be milled at each bolt location in order to that may

  a compression ring 152 is housed there (only one is shown

  which presses the material of the profile part

37 inside the countersink.

  The clamping pieces 146, 148 are bent over their upper ends and define an opening 154 o can house a pin 156 secured to the rocking anvil 144; the journal 156 makes it possible to accommodate the spring 142, mounted between two spring sockets 158, 160. The lower spring socket 158 is mounted on a U-shaped piece 162, itself mounted on the bar 140. The anvil of 'shaking 144 also includes an upper part 164, adapted to receive the shaking jerks of a vertical drop rod hammer 60 (Figure 4) of known type. The length of the journal 156 is such that the latter remains at a certain distance

  spring bushing 158 during jerking

  lement. It should be noted that, during the operation of the filter, the shaking jerks received by the anvil 144 are transmitted directly to the profile part 37, by means of clamping pieces 146, 148, obviously with minimum dissipation d energy in the bar 140, due to the elastic mounting between the bar

  140 and the profile part 37 supplied by the spring 142.

  In another embodiment (not shown), two parts of symmetrically spaced intermediate sections

  36 of each collecting electrode 12 are mounted elastic-

  ment on the bar 140 using springs corresponding to the springs 142, and comprising shaking anvils corresponding to the anvils 144, of the same axis as the springs 142. In this case, the parts of external sections 37 and the rest of the sections of sections 36 are rigidly

attached to the bar 140.

  In another embodiment, two electrodes collected

  adjacent trices are connected by their vertices to two transverse pieces at the opposite ends of the electrodes; in this case, the shaking anvils are provided in the center of the cross pieces, as indicated for example

  in GB-1 252 452 (Lodge-Cottrell Limited).

  The apparatus for shaking the collecting electrodes 16 (FIGS. 1 and 4) comprises shaking assemblies

  16a, 16b adjacent to the opposite ends of the bars 140.

  The assembly 16a will be described with reference more precisely

in Figure 4.

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  The rocking assembly 16a includes a horizontal shaft

  52 located outside the box 2 above the cover 7. The rear

  bre 52 is rotatably mounted in bearings 54 (only one is shown) each mounted on a bent support structure 56 fixed to the cover 7; the tree 52 is animated by a

  motor 200 (figure 1). On the shaft 52 is fixed a plura-

  a set of operating pins 58 (only two of them are shown), each being arranged to control one of the drop rod hammers 60; every

  anvil 144 is associated with a drop rod hammer 60.

  Each hammer 60 can slide in a vertical slide 62 which passes through the cover 7 to the appropriate anvil 144. The hammer 60 is also housed in a ring 64 mounted on the support structure 56. The upper end of the hammer 60 includes a disc 66 suitable for cooperating with

  the appropriate operating spindle 58. During operation

  ment of the device, the shaft 52 rotates and each actuating spindle 58 engages with the disc 66 opposite the latter, which causes an elevation

  hammer 60 in the high position. The tree 52, in conti-

  Naked to turn, then causes the actuating spindle 58 to click into place, and the hammer 60 falls, producing a shaking jerk on the anvil 144; this is repeated

  as the shaft 52 rotates.

  In the embodiment shown in FIG. 5, the rocking anvil 244 is a rectangular block tightened between external clamping pieces 248; the anvil 244 does not overflow onto the external clamping parts

  248 and is aligned with these in the upper part

  - higher. The internal clamps 246 and the profiled part 237 lead to the block 244. The block 244 is hollowed out at 300, in order to receive the spring 242. A positioning pin of the spring 256 is mounted in the positioning plate 258, fixed on the 240 bar and extends

  by an opening 241 inside the bar 240.

  It has been noted that the embodiments of the invention

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  tion are particularly advantageous when the adjacent profiles of each collector electrode are largely

spaced from each other.

Claims (10)

Claims.   1. Set of collecting electrode for electrostatic filter   tick comprising a collector electrode suspended from a support bar situated on the upper edge of the collector electrode, means for transmitting shaking jerks to the collector electrode, characterized in   that the collecting electrode (12) is suspended elastic-   the support bar (140) and that the shock   are directly transmitted to the collecting electrode   where it hangs elastically.   2. electrode assembly according to claim 1, characterized in that the collector electrode (12) comprises a generally flat panel part and a plurality of profile parts directed downwards (36, 37), each of these profiles also being located on each side of the part   flat panel (34); and in that the means for trans-   putting the shaking jerks comprise at least one shaking anvil (144, 244) which is arranged so that the shaking jerks applied to the anvil are transmitted directly to one of the parts of the profile (37) , said profiled part (37) being aligned with the anvil (144, 244).   3. electrode assembly according to claim 2, characterized in that the rest of the profile parts (36) which are not aligned with the anvils are fixed so   rigid to the support bar (140).   4. electrode assembly according to one of claims   1, 2 and 3, characterized in that the means for transmitting   the shaking jerks comprise a plurality of ent-   shaking anvils (144, 244) symmetrically spaced   along the upper edge of the collecting electrode (12).   5. electrode assembly according to claim 4, characterized in that the collecting electrode is held by a 258694Z   plurality of springs (142, 242), each of these springs acting between the support bar (140, 240) and one of the rocking anvils (144, 244), the anvils being   located above the support bar.   6. electrode assembly according to claim 5, character-   risé in that the springs (142, 242) are coaxial with   the shaking anvils (144, 244).   7. An electrode assembly according to claim 5, character-   laughed in that each rocking anvil (140) includes a pin (156) which allows the spring to be positioned   (152) acting between the anvil and the support bar (140).   8. An electrode assembly according to claim 5, character-   in that each shaking anvil (244) is avoided   designed to receive the spring (242) acting between the anvil and the support bar (240).   9. electrode assembly according to one of claims   1 to 8, characterized in that the collecting electrode is suspended in an elastic manner in two places located at its opposite ends.   10. electrode assembly according to one of claims   1 to 9, characterized in that the shaking jerks   are produced by drop hammer hammers (60).