Continuous clean bag filter apparatus and method

• US 4,411,674 A
• Filed: 06/02/1981
• Issued: 10/25/1983
• Est. Priority Date: 06/02/1981
• Status: Expired due to Fees

• Current Assignee: Ohio Blow Pipe Co.
• Original Assignee: Ohio Blow Pipe Co.
• Inventors: Forgac, John P.
• Primary Examiner(s): Prunner, Kathleen J.
• Application Number:
  US06/269,631
• Time in Patent Office: 875 Days
• Field of Search: 55/315, 55/338, 55/431, 55/466, 55/304, 55/341 NT, 55/96-97, 55/DIG. 32, 406/88, 406/90, 406/94, 406/139, 406/146, 406/171-172
• US Class Current: 55/304
• CPC Class Codes: B01D 46/04 Cleaning filters
• CPC Class Codes: B01D 46/444 by flow measuring
• CPC Class Codes: B01D 46/446 by pressure measuring
• CPC Class Codes: B01D 46/48 Removing dust other than cleaning filters , e.g. by using collecting trays
• CPC Class Codes: B01D 46/62 connected in series
• CPC Class Codes: B01D 46/76 involving vibrations
• CPC Class Codes: B01D 50/20 Combinations of devices covered by groups B01D45/00 and B01D46/00
• CPC Class Codes: Y10S 55/32 Gaseous fluid conveying

Abstract

A continuously cleaned bag filter provides a second filter stage for removing dust from air discharged from a cyclone or other primary separator. The primary separator removes the majority of particulate matter from air delivered thereto. In the bag filter dust is filtered from the air, which is discharged through the filter walls. The filtered dust is conveyed along the bottom of the bag filter by an air conveyor and is recirculated back to the primary separator for removal thereat. The air conveyor and a recirculating air blower, the latter providing impetus to carry dust back to the primary separator, are balanced relative to the inflowing air to the bag filter from the primary separator; such balance prevents excessive back-pressure or negative pressure in the filter bags that would otherwise interfere with ordinary air discharge therefrom.

Claims

1. Continuous clean bag filter apparatus for use with a primary separator disposed relatively upstream thereof, comprising inlet means for receiving a fluid carrier and particulate matter carried thereby vertically disposed bag filter means open at opposite ends pressurized by such fluid carrier for filtering particulate matter from such fluid carrier while at least a substantial quantity of such fluid carrier discharges through a wall portion of said bag filter means, fluid conveyor means for continuously conveying from said bag filtemeans that particulate matter filtered from such fluid carrier, and outlet means for discharging particulate matter from said fluid conveyor means, said fluid conveyor means comprising a controlled fluid flow means for delivering a controlled fluid flow to convey to said outlet mean that particulate matter filtered from such fluid carrier by said bag filter means without interfering with and substantially independently of the passage of such fluid carrier through said wall portion of said bag filter means, and said outlet means comprising further controlled fluid flow means for producing a further controlled fluid flow to convey that particulate matter received from said fluid conveyor means downstream thereof, and balancing means for balancing said further controlled fluid flow means with respect to the fluid pressure in said bag filter means and the fluid pressure of said fluid conveyor means to provide such further controlled fluid flow that does not interfere substantially with operation of said bag filter means and further comprising collecting means for collecting particulate matter from said bag filter means, and wherein said controlled fluid flow means of said fluid conveyor means comprises blower means for establishing an air flow, plenum means for conducting such air flow proximate said collecting means, and flow directing means for directing at least some of such air flow in said collecting means.

2. The apparatus of claim 1, said bag filter means comprising filter bags.

3. The apparatus of claim 2, said bag filter means further comprising housing means for supporting said filter bags.

4. The apparatus of claim 2, said inlet means comprising a distribution chamber for substantially evenly distributing such fluid carrier and particulate matter to respective filter bags.

5. The apparatus of claim 4, each of said filter bags being open at the top and at the bottom thereof, and wherein such fluid carrier comprises air and each of said filter bags has porous side walls to permit air flow therethrough while retaining particulate matter within the interior thereof.

6. The apparatus of claim 1, said inlet means comprising duct means for conveying such fluid carrier and particulate matter to said bag filter means.

7. The apparatus of claim 1, said collecting means being located beneath said bag filter means, being elongated, and being substantially tapered from a relatively wide upper portion to a relatively narrower lower portion, said plenum means being positioned below said collecting means, and said flow directing means comprising a slatted wall between said collecting means and said plenum means.

8. The apparatus of claim 7, wherein said blower means is positioned at one end of said plenum means for blowing air toward the other end of said plenum means to provide such air flow, said slatted wall comprising plural overlapping wall slats, respective pairs of adjacent overlapping wall slats having respective flow openings therebetween, and a direction control slat proximate the end of said plenum means remote from said blower means.

9. The apparatus of claim 1, further comprising shaking means for shaking said bag filter means to cause particulate matter therein to drop toward a bottom portion thereof.

10. Continuous clean bag filter apparatus for use with a primary separator disposed relatively upstream thereof, comprising inlet means for receiving a fluid carrier and particulate matter carried thereby, vertically disposed bag filter means open at both ends for filtering particulate matter from such fluid carrier, said bag filter means including a wall means permeable to such fluid carrier for passing at least some of such fluid carrier therethrough while not passing such particulmatter therethrough, and fluid conveyor means for continuously conveying particlate matter filtered from such fluid carrier from said bag filter means, further comprising collecting means for collecting particulate matter from said bag filter means, and wherein said fluid conveyor means comprises blower means for establishing an air flow, plenum means for conducting such air flow proximate said collecting means, and flow directing means for directing at least some of such air flow in said collecting means, said collecting means being located beneath said bag filter means, being elongated, and being substantially tapered from a relatively wide upper portion to a relatively narrower lower portion, said plenum means being positioned below said collecting means, and said flow directing means comprising a slatted wall between said collecting means and said plenum means, wherein said blower means is positioned at one end of said plenum means for blowing air toward the other end of said plenum means to provide such air flow, said slatted wall comprising plural overlapping wall slats, respective pairs of adjacent overlapping wall slats having respective flow openings therebetween, and a direction control slat proximate the end of said plenum means remote from said blower means, said filter means comprising a housing, said fluid conveyor means being positioned proximate the bottom of said housing, outlet means for conducting particulate matter from said collecting means and conveyor means, and said direction control slat comprising slat means positioned to direct air directly from said plenum means into said outlet means.

11. The apparatus of claim 10, further comprising recirculating means for recirculating particulate matter from said outlet means to such primary separator.

12. The apparatus of claim 11, wherein said fluid carrier comprises air, and wherein said blower means and recirculating means are balanced with respect to each other and with respect to such fluid carrier in said bag filter means to provide air flow that does not interfere substantially with operation of said bag filter means releasing air through side walls thereof.

13. A filter system, comprising a primary separator means for filtering particulate matter from a fluid carrier, filter means for filtering particulate matter from such fluid carrier discharged from said primary separator means, and recirculating means for recirculating back to said primary separator means particulate matter filtered from such fluid carrier by said filter means, said filter means comprising a vertically disposed bag filter, said recirculating means comprising a recirculating blower and a recirculating duct means for connecting said recirculating blower with said primary separator means, such fluid carrier comprising air, said filter means havng a top, sides and a bottom and comprising porous filter means for emitting air at the sides thereof, inlet means for inletting the air carrying particulate matter from said primary separator means to the top of said filter means, said bottom of said filter means being open, and further comprising conveyor means for conveying particulate matter from beneath said filter means to said recirculating means, said recirculating means being balanced with respect to at least air pressure and flow in said filter means so as not substantially to interfere with operation of said filter means releasing air through the porous sides thereof, said conveyor means comprising an air conveyor, further comprising collecting means for collecting particulate matter from said filter means, said air conveyor comprising blower means for establishing an air flow, plenum means for conducting such air flow proximate said collecting means, and flow directing means for directing at least some of such air flow in said collecting means, said collecting means being located beneath said filter means, being elongated, and being substantially tapered from a relatively wide upper portion to a relatively narrower lower portion, said plenum means being positioned below said collecting means, and said flow directing means comprising a slatted wall between said collecting means and said plenum means.

14. The system of claim 13, said primary separator means comprising a cyclone separator.

15. A vertically disposed bag filter open at opposite ends and fluid conveyor for removing particulate matter from a pressurized collection zonthe bag filter, said fluid conveyor comprising a fluid plenum means for receivng an inlet flow of fluid, wall means for separating said plenum means from such bag filter, plural opening means in said wall means for directing a flow of such fluid from said plenum means into such pressurized collection zone in a direction substantially parallel to said wall means to carry particulate matter along substantially parallel to said wall means, and outlet means for discharging such fluid and particulate matter carried thereby out from such collection zone, wherein said collection zone is located at the bottom of such bag filter further comprising blower means for establishing such fluid flow, means for connecting said blower means to said fluid plenum means, and said wall means being positioned to separate said plenum means from such collection zone, said wall means comprising a plurality of overlapping slats having respctive ones of said plural opening means therebetween for directing such fluid in a prescribed direction, said blower means being positioned at one end of said fluid plenum means for blowing such fluid toward the other end of said plenum means, and said walls means further comprising a direction control slat at the opposite end of said fluid plenum means from said blower means positioned to direct such fluid directly from said fluid plenum means into said outlet means.