US3668836A - Electrostatic precipitator - Google Patents

Electrostatic precipitator Download PDF

Info

Publication number
US3668836A
US3668836A US4947A US3668836DA US3668836A US 3668836 A US3668836 A US 3668836A US 4947 A US4947 A US 4947A US 3668836D A US3668836D A US 3668836DA US 3668836 A US3668836 A US 3668836A
Authority
US
United States
Prior art keywords
wires
duct
banks
plates
gas stream
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US4947A
Other languages
English (en)
Inventor
Harry L Richardson
Robert C Craig
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Environmental Services Inc
Chemical Construction Corp
Original Assignee
Chemical Construction Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chemical Construction Corp filed Critical Chemical Construction Corp
Application granted granted Critical
Publication of US3668836A publication Critical patent/US3668836A/en
Assigned to GENERAL ELECTRIC COMPANY, A CORP. OF NY. reassignment GENERAL ELECTRIC COMPANY, A CORP. OF NY. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ENVIROTECH CORPORATION
Assigned to GENERAL ELECTRIC ENVIRONMENTAL SERVICES, INCORPORATED reassignment GENERAL ELECTRIC ENVIRONMENTAL SERVICES, INCORPORATED ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: GENERAL ELECTRIC COMPANY A NY CORP.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/02—Plant or installations having external electricity supply
    • B03C3/04—Plant or installations having external electricity supply dry type
    • B03C3/09—Plant or installations having external electricity supply dry type characterised by presence of stationary flat electrodes arranged with their flat surfaces at right angles to the gas stream

Definitions

  • ABSTRACT References cued An electrical or electrostatic precipitator is provided with a UNITED STATES PATENTS grounded collector plate upstream of the electrically charged wires. The plate is juxtaposed adjacent to the wires and pro- 1,343,482 6/1920 Schmidt et a1.
  • the invention relates to the removal of entrained discrete particles from a gas stream by electrical or electrostatic precipitation.
  • the entrained discrete particles may consist of liquid droplets or solid particles such as fume, dust, soot, fly ash or the like, chemical particles from a chemical process gas stream such as the off-gas from a fluid bed reactor or ore roaster, etc.
  • the invention is generally applicable to the treating of diverse gas streams, such as flue gas, a chemical process gas stream, or the tail gas from a chemical process, and is especially useful in the prevention of air pollution due to the discharge of waste gas streams containing entrained discrete particles into the atmosphere.
  • diverse gas streams such as flue gas, a chemical process gas stream, or the tail gas from a chemical process
  • a gas or vapor stream laden with entrained discrete particles consisting of components such as those described supra or the like is passed through a duct or similar gas passage means such as a conduit or elongated container.
  • a first perforated plate is transversely disposed in the duct, so that the gas stream initially passes through the openings in the first plate, which is succeeded by alternate juxtaposed transverse banks of parallel spaced apart wires and secondary perforated plates.
  • the plates are grounded and the wires are provided with an electrical or electrostatic charge, so that a high voltage potential is maintained between the ionizing wires and the grounded plates, and the entrained discrete particles are deposited from the gas stream onto the plates, due to an electrostatic precipitation mechanism in which the particles receive a charge from the wires and are discharged by and onto the plates. It has been determined that the provision of the first plate prior to the initial wire or bank of parallel wires is highly advantageous, since a considerable proportion of particles will deposit on the first plate upstream of the initial bank of wires, and thus the overall particle collection efficiency and removal of particles from the gas stream are greatly improved.
  • Another object is to provide an improved electrical or electrostatic precipitator.
  • a further object is to increase the particles removal efficiency of an electrostatic precipitator.
  • An additional object is to remove entrained discrete particles from a gas stream in an electrostatic precipitator by the provision of a collector plate upstream of the first bank of ionizing wires.
  • FIG. 1 is a sectional elevation view of one embodiment of the invention
  • FIG. 2 is a sectional plan view of FIG. 1, taken on section 2-2,
  • FIG. 3 is an isometric view of the preferred embodiment of the collector plates shown in FIGS. 1 and 2, and
  • FIG. 4 is an isometric view of an alternative embodiment and species of collector plate, showing associated ionizing wires.
  • a gaseous or vaporous stream 1 containing entrained discrete particles is passed via fan or blower 2 as stream 3 into the duct 4, which in this embodiment of the invention is generally horizontally oriented and of a rectangular or square cross-section.
  • the duct 4 is connected to ground via ground wire or connection rod 5.
  • the gas stream within duct 4 passes initially through the spaced openings in the foraminous collector plate 6, which is disposed upstream of and adjacent to the primary ionizer wires or rods 7.
  • the elements 7 are provided with an electrical charge or potential or an electrostatic charge by means of charge lead wire 8 which connects via an insulated connection through duct 4 to wire 7.
  • Wire 8 Electrical potential is furnished to wire 8 via the main high potential wire or busbar line 9, which extends from a suitable high potential source 10, which may be a transformer and rectifier combination or the like.
  • Unit 10 furnishes a high voltage potential, either negative or positive, to busbar 9, and the opposite polarity of unit 10 may be grounded, either via duct 4 or directly to ground.
  • the influence of the electrical charge imparted to wire 7 causes the entrained discrete particles in the gas stream, which may be either liquid droplets or solid particles such as soot, dust, fly ash, fume, fog or the like, to attain an electrical charge relative to ground, and a portion of the discrete particles are discharged by and deposited onto the primary collector plate 6.
  • the gas stream within duct 4 next passes in series through the openings in the plurality of downstream foraminous secondary collector plates 11, between which are disposed the secondary potential or ionizing wires 12, so that an alternative series of ionizing wires or rods 12 and secondary collector plates 11 are provided.
  • An electrical charge or potential is provided on wires 12 via secondary lead wires 13, which extend from busbar 9 through duct 4 via an insulated connection to the wires 12. Further amounts of discrete particles are deposited from the gas stream onto the collector plates 11.
  • a preferred configuration of duct 4 is shown in FIG. 1, in which the downstream portion 14 of duct 4 increases progressively in cross-sectional area in the direction of gas flow, so that the linear velocity of gas flow decreases in section 14.
  • the decrease in gas flow in section 14 aids in removal of discrete particles by preventing re-entrainment of deposited material from plates 11 into the gas stream due to turbulence or high gas velocity.
  • the final purified or cleansed gas stream now having a depleted or negligible content of entrained discrete particles, flows into outlet duct or conduit 15, which extends from section 14 and passes the gas stream 16 to suitable utilization or atmospheric discharge via a stack or the like, not shown.
  • FIG. 2 a sectional plan view of the apparatus is shown, which further illustrates the arrangement of the perforated or foraminous primary collector plate 6, the ancillary or secondary collector plates 11, and the linear banks of parallel ionizing wires or rods 7 and 12 disposed between collector plates.
  • FIG. 3 shows a typical collector plate provided with circular openings 17 for gas flow.
  • FIG. 4 shows an alternative embodiment of a collector plate, in which vertical slits 18 are provided for gas flow, with the slits 18 preferably being parallel with the ionizing wires or rods 7, which are juxtaposed and spaced from plate 6.
  • the duct 4 and appurtenances such as section 14 may be horizontally or vertically oriented, or mounted in an inclined position. In all such cases the collector plates 6 and 11 and associated ionizing wires 7 and 12 will extend substantially transversely within the duct.
  • a single downstream collector plate 11 disposed adjacent to wire 7 may be provided in some cases, in which case the banks of wires 12 and associated downstream collector plates may be omitted.
  • Suitable rapping or shaking devices or means will usually be provided in practice, to intermittently or continuously agitate or shake the collector plates to remove deposited material. Rapping devices may also be provided for wires 7 and 12.
  • the plates and wires may be intermittently washed down with a suitable wash liquid such as water or a solvent for the deposited discrete particles.
  • a suitable wash liquid such as water or a solvent for the deposited discrete particles.
  • the foraminous plates 6 and 11 may be provided with openings which are circular, elliptical, square, triangular or the like, or slits such as shown in FIG. 4 may be provided in practice.
  • the collector plates may even consist of a series of flat parallel juxtaposed strips, preferably with each strip oriented opposite to an ionizing wire.
  • Equal distribution of voltage to the various wire banks 6 and 12 may be assured in practice by the provision of various electrical chokes or the like.
  • Half-wave or full wave electrical potential may be provided in suitable instances.
  • the fan or blower 2 will be provided downstream of the apparatus so that the blower draws the impurity-laden gas stream through the unit and thus handles only cleaned gas or vapor. 1n power plants, this arrangement is required by insurers, with the fan or blower 2 handling only flue gas free offly ash.
  • test apparatus was provided with five parallel banks of ionizer wires, with each bank of wires being followed by a grounded perforated collector plate. A voltage of 40 kv. was impressed on the wires and the apparatus was operated with an additional primary collector plate prior to the first bank of wires. An air stream laden with entrained particles of fly ash dust was passed through the apparatus and the collection efficiency was measured. The apparatus was then operated in a second test without the primary collector plate and the collection efficiency was measured. Following are the test results.
  • An apparatus for the electrostatic removal of entrained particles from a gas stream which comprises a duct, means to pass a feed gas stream containing entrained discrete particles into said duct, said duct being of constant cross-sectional area in the direction of gas flow over the initial portion of the length of said duct and of progressively increased cross-sectional area in the direction of gas flow over the terminal portion of the length of said duct, whereby the linear velocity of flow of said gas stream is substantially constant through said initial duct portion and decreases through said terminal duct portion, a first plurality of parallel spaced apart linear banks of wires, each of said first banks containing a plurality of parallel spaced apart electrically charged wires and extending transversely into said initial portion of said duct, means to continuously maintain an electrical potential relative to ground on each of the wires in each of said first banks of wires, a primary foraminous plate, said primary plate being transversely disposed within said initial portion of said duct upstream of said first banks of wires and juxtaposed adjacent to the first bank of said

Landscapes

  • Electrostatic Separation (AREA)
US4947A 1970-01-22 1970-01-22 Electrostatic precipitator Expired - Lifetime US3668836A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US494770A 1970-01-22 1970-01-22

Publications (1)

Publication Number Publication Date
US3668836A true US3668836A (en) 1972-06-13

Family

ID=21713338

Family Applications (1)

Application Number Title Priority Date Filing Date
US4947A Expired - Lifetime US3668836A (en) 1970-01-22 1970-01-22 Electrostatic precipitator

Country Status (6)

Country Link
US (1) US3668836A (enExample)
BE (1) BE761889A (enExample)
BR (1) BR7100388D0 (enExample)
DE (1) DE2103022A1 (enExample)
FR (1) FR2077612A7 (enExample)
NL (1) NL7100925A (enExample)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3973932A (en) * 1974-04-23 1976-08-10 Ab Lectrostatic Apparatus for electrodynamically separating particles from a gas
US4496375A (en) * 1981-07-13 1985-01-29 Vantine Allan D Le An electrostatic air cleaning device having ionization apparatus which causes the air to flow therethrough
US4698074A (en) * 1987-02-09 1987-10-06 Cumming Corporation Air cleaning apparatus
US4790861A (en) * 1986-06-20 1988-12-13 Nec Automation, Ltd. Ashtray
US5059219A (en) * 1990-09-26 1991-10-22 The United States Goverment As Represented By The Administrator Of The Environmental Protection Agency Electroprecipitator with alternating charging and short collector sections
US5322550A (en) * 1992-02-28 1994-06-21 Samsung Electronics, Co., Ltd. Electrical dust collector
US5695549A (en) * 1996-04-05 1997-12-09 Environmental Elements Corp. System for removing fine particulates from a gas stream
US5707428A (en) * 1995-08-07 1998-01-13 Environmental Elements Corp. Laminar flow electrostatic precipitation system
US5961693A (en) * 1997-04-10 1999-10-05 Electric Power Research Institute, Incorporated Electrostatic separator for separating solid particles from a gas stream
US6287368B1 (en) * 1989-08-25 2001-09-11 Oy Airtunnel Ltd. Apparatus for the purification of air flue gases, or equivalent
US20040149132A1 (en) * 2002-12-09 2004-08-05 Hajrudin Pasic Electrostatic sieving precipitator
EP1504804A1 (en) * 2003-08-01 2005-02-09 Eurotecno S.R.L. Arrangement for partial recirculation of exhaust gases from heating boilers powered by gas or other fuels
US20060137528A1 (en) * 2004-12-29 2006-06-29 Ms. Setsu Anzai Electrostatic precipitator
US20110056372A1 (en) * 2009-09-04 2011-03-10 Rutgers, The State University Of New Jersey Electrostatic screen device and method for emission control
US8608826B2 (en) 2011-04-11 2013-12-17 King Fahd University Of Petroleum And Minerals Method of modeling fly ash collection efficiency in wire-duct electrostatic precipitators
US20240269692A1 (en) * 2020-09-18 2024-08-15 Shannon Smith-Crowley Direct air carbon capture system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2644787C2 (de) * 1976-10-04 1982-10-28 Kievskij institut inženerov graždanskoj aviacii, Kiev Vorrichtung zur Reinigung dielektrischer Flüssigkeiten von Feststoffverunreinigungen in einem elektrischen Gleichstromfeld

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE519391A (enExample) *
US1343482A (en) * 1914-03-23 1920-06-15 Int Precipitation Co Apparatus for separating suspended particles from gases
US1381660A (en) * 1918-10-31 1921-06-14 Rathbun Ross Buxton Method of removing solids suspended in moving gases
GB167939A (en) * 1920-06-29 1921-08-25 Int Precipitation Co Improvements in apparatus for electrical treatment of gases
US1444997A (en) * 1920-03-22 1923-02-13 Int Precipitation Co Apparatus for the electrical separation of suspended material from gases
US1479271A (en) * 1919-12-15 1924-01-01 Int Precipitation Co Method and apparatus for separating suspended particles from gases
DE459961C (de) * 1919-12-15 1928-05-16 Metallbank & Metallurg Ges Ag Anlage zur elektrischen Abscheidung von Schwebekoerpern aus Gasen mit Spruehelektroden und gegenpoligen (geerdeten) rohrfoermigen Niederschlagselektroden
DE471795C (de) * 1923-03-02 1929-02-21 Siemens Schuckertwerke Akt Ges Elektrische Staubniederschlagsanlage
FR1334881A (fr) * 1962-10-03 1963-08-09 Omnical Gmbh Procédé et dispositif pour la séparation de molécules en suspension, à partir de gaz
GB959655A (en) * 1962-04-03 1964-06-03 Alex Rammelmeyer Improvements in or relating to electro dust separators

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE519391A (enExample) *
US1343482A (en) * 1914-03-23 1920-06-15 Int Precipitation Co Apparatus for separating suspended particles from gases
US1381660A (en) * 1918-10-31 1921-06-14 Rathbun Ross Buxton Method of removing solids suspended in moving gases
US1479271A (en) * 1919-12-15 1924-01-01 Int Precipitation Co Method and apparatus for separating suspended particles from gases
DE459961C (de) * 1919-12-15 1928-05-16 Metallbank & Metallurg Ges Ag Anlage zur elektrischen Abscheidung von Schwebekoerpern aus Gasen mit Spruehelektroden und gegenpoligen (geerdeten) rohrfoermigen Niederschlagselektroden
US1444997A (en) * 1920-03-22 1923-02-13 Int Precipitation Co Apparatus for the electrical separation of suspended material from gases
GB167939A (en) * 1920-06-29 1921-08-25 Int Precipitation Co Improvements in apparatus for electrical treatment of gases
DE471795C (de) * 1923-03-02 1929-02-21 Siemens Schuckertwerke Akt Ges Elektrische Staubniederschlagsanlage
GB959655A (en) * 1962-04-03 1964-06-03 Alex Rammelmeyer Improvements in or relating to electro dust separators
FR1334881A (fr) * 1962-10-03 1963-08-09 Omnical Gmbh Procédé et dispositif pour la séparation de molécules en suspension, à partir de gaz

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
German printed Application No. 1,078,096, printed March 24, 1960, (2 pages specification, 1 sheet drawing) *

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3973932A (en) * 1974-04-23 1976-08-10 Ab Lectrostatic Apparatus for electrodynamically separating particles from a gas
US4496375A (en) * 1981-07-13 1985-01-29 Vantine Allan D Le An electrostatic air cleaning device having ionization apparatus which causes the air to flow therethrough
US4790861A (en) * 1986-06-20 1988-12-13 Nec Automation, Ltd. Ashtray
US4698074A (en) * 1987-02-09 1987-10-06 Cumming Corporation Air cleaning apparatus
US6287368B1 (en) * 1989-08-25 2001-09-11 Oy Airtunnel Ltd. Apparatus for the purification of air flue gases, or equivalent
EP0550462B1 (en) * 1990-09-26 1997-10-08 United States Environmental Protection Agency Electroprecipitator with alternating charging and short collector sections
US5059219A (en) * 1990-09-26 1991-10-22 The United States Goverment As Represented By The Administrator Of The Environmental Protection Agency Electroprecipitator with alternating charging and short collector sections
AU664069B2 (en) * 1992-02-28 1995-11-02 Samsung Electronics Co., Ltd. Electrical dust collector
US5322550A (en) * 1992-02-28 1994-06-21 Samsung Electronics, Co., Ltd. Electrical dust collector
US5707428A (en) * 1995-08-07 1998-01-13 Environmental Elements Corp. Laminar flow electrostatic precipitation system
US5695549A (en) * 1996-04-05 1997-12-09 Environmental Elements Corp. System for removing fine particulates from a gas stream
US5961693A (en) * 1997-04-10 1999-10-05 Electric Power Research Institute, Incorporated Electrostatic separator for separating solid particles from a gas stream
US6096118A (en) * 1997-04-10 2000-08-01 Electric Power Research Institute, Incorporated Electrostatic separator for separating solid particles from a gas stream
US20040149132A1 (en) * 2002-12-09 2004-08-05 Hajrudin Pasic Electrostatic sieving precipitator
US6878192B2 (en) 2002-12-09 2005-04-12 Ohio University Electrostatic sieving precipitator
EP1504804A1 (en) * 2003-08-01 2005-02-09 Eurotecno S.R.L. Arrangement for partial recirculation of exhaust gases from heating boilers powered by gas or other fuels
US20060137528A1 (en) * 2004-12-29 2006-06-29 Ms. Setsu Anzai Electrostatic precipitator
WO2006070935A1 (en) * 2004-12-29 2006-07-06 Anzai, Setsu Electrostatic precipitator
US7261765B2 (en) 2004-12-29 2007-08-28 Anzai, Setsu Electrostatic precipitator
US20110056372A1 (en) * 2009-09-04 2011-03-10 Rutgers, The State University Of New Jersey Electrostatic screen device and method for emission control
US8721767B2 (en) * 2009-09-04 2014-05-13 Rutgers, The State University Of New Jersey Electrostatic screen device and method for emission control
US8608826B2 (en) 2011-04-11 2013-12-17 King Fahd University Of Petroleum And Minerals Method of modeling fly ash collection efficiency in wire-duct electrostatic precipitators
US20240269692A1 (en) * 2020-09-18 2024-08-15 Shannon Smith-Crowley Direct air carbon capture system
US12453975B2 (en) * 2020-09-18 2025-10-28 Shannon Smith-Crowley Direct air carbon capture system

Also Published As

Publication number Publication date
NL7100925A (enExample) 1971-07-26
BR7100388D0 (pt) 1973-02-13
BE761889A (fr) 1971-07-22
FR2077612A7 (enExample) 1971-10-29
DE2103022A1 (de) 1971-07-29

Similar Documents

Publication Publication Date Title
US3668836A (en) Electrostatic precipitator
US2756842A (en) Electrostatic gas cleaning method
US5217511A (en) Enhancement of electrostatic precipitation with electrostatically augmented fabric filtration
US4357150A (en) High-efficiency electrostatic air filter device
US4443234A (en) Device at a dust filter
US4354858A (en) Method for filtering particulates
US3733784A (en) Electro-bag dust collector
US4308036A (en) Filter apparatus and method for collecting fly ash and fine dust
US3729898A (en) Removal of entrained matter from gas streams
US3958958A (en) Method for electrostatic removal of particulate from a gas stream
US6878192B2 (en) Electrostatic sieving precipitator
US4374652A (en) Filter apparatus and method for collecting fly ash and fine dust
US4293319A (en) Electrostatic precipitator apparatus using liquid collection electrodes
US3874858A (en) Method and apparatus for electrostatic removal of particulate from a gas stream
US6932857B1 (en) Multi-stage collector and method of operation
JPH0476738B2 (enExample)
US3704572A (en) Electrostatic precipitator system
US3633337A (en) Gas-handling method and apparatus
US3896347A (en) Corona wind generating device
US2712858A (en) Apparatus for separating suspended materials from gases
US2973054A (en) Gas cleaning unit
US2556982A (en) Electrostatic precipitator
US3853511A (en) Electrical precipitating apparatus
US4326861A (en) Dust-collecting assembly for electrostatic precipitator
US4244709A (en) High intensity ionization-electrostatic precipitation system for particle removal and method of operation

Legal Events

Date Code Title Description
AS Assignment

Owner name: GENERAL ELECTRIC COMPANY, A CORP. OF NY., NEW YORK

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:ENVIROTECH CORPORATION;REEL/FRAME:003933/0138

Effective date: 19810425

AS Assignment

Owner name: GENERAL ELECTRIC ENVIRONMENTAL SERVICES, INCORPORA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:GENERAL ELECTRIC COMPANY A NY CORP.;REEL/FRAME:004118/0578

Effective date: 19830217

STCK Information on status: patent revival

Free format text: ABANDONED - RESTORED