Pulsing Or Time-varying Electric Field (e.g., Ac, Pulsed Dc, Etc.) Patents (Class 95/81)
  • Patent number: 9180466
    Abstract: A combination discharge reactor for decomposing waste gas is disclosed is disclosed to include a housing with a gas inlet and gas outlets, and multiple processing units mounted in the housing. Each processing unit includes a support structure consisting of brackets and support rods, a rod electrode mounted in the bracket, and a tubular electrode mounted in the brackets and surrounding the rod electrode.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: November 10, 2015
    Inventor: Hua-Ming Liu
  • Patent number: 8808433
    Abstract: A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: August 19, 2014
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: Roger D. Aines, William L. Bourcier
  • Patent number: 8623116
    Abstract: Provided is a method of controlling the operation of an electrostatic precipitator (6) using a control strategy for a power to be applied between at least one collecting electrode (28) and at least one discharge electrode (26). The control strategy is directed to controlling, directly or indirectly, a power range and/or a power ramping rate. As such, the temperature of a process gas is measured. When the control strategy controls a power range, a power range is selected based on the measured temperature, an upper limit value of the power range being lower at a high temperature of said process gas, than at a low temperature. When the control strategy controls a power ramping rate, a power ramping rate is selected based on the measured temperature, a power ramping rate being lower at a high process gas temperature, than at a low process gas temperature.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: January 7, 2014
    Assignee: ALSTOM Technology Ltd
    Inventor: Anders Nils Gustav Karlsson
  • Publication number: 20130255482
    Abstract: Technologies are presented for applying electrical energy to a combustion reaction to produce agglomerated combustion particulates. For example, a system may include: one or more electrodes configured to apply electrical energy to a combustion reaction; a combustion zone configured to support the combustion reaction of a fuel at a fuel source; and an electrical power source operatively coupled to the one or more electrodes and configured to apply electrical energy to the combustion reaction. The combustion reaction is controlled to produce a distribution of agglomerated combustion particulates characterized by an increase in at least one of an average particulate diameter or an average particulate mass.
    Type: Application
    Filed: March 25, 2013
    Publication date: October 3, 2013
    Inventor: DAVID B. GOODSON
  • Patent number: 8518163
    Abstract: A device having advantages in terms of equipment maintenance, since it provides maximum limitation of the onset of electric arcing between the electrodes, including a vertical cathode equipped with emissive points, these points being offset at an angle from each other from one plane to another, so as to be optimally distributed in space. One embodiment using two planar anodes, between which several vertical cathodes are arranged equipped with points, is also envisaged.
    Type: Grant
    Filed: February 17, 2009
    Date of Patent: August 27, 2013
    Assignees: Commissariat a l'Energie Atomique et aux Energies Alternatives, Universite de Pau et Des Pays de L'Adour
    Inventors: Florent Lemont, Antoine Silvestre de Ferron, Thierry Reess, Aldo Russello
  • Patent number: 8449650
    Abstract: Gases are stored, separated, and/or concentrated. An electric field is applied across a porous dielectric adsorbent material. A gas component from a gas mixture may be selectively separated inside the energized dielectric. Gas is stored in the energized dielectric for as long as the dielectric is energized. The energized dielectric selectively separates, or concentrates, a gas component of the gas mixture. When the potential is removed, gas from inside the dielectric is released.
    Type: Grant
    Filed: June 15, 2010
    Date of Patent: May 28, 2013
    Assignee: Los Alamos National Security, LLC
    Inventors: Robert P. Currier, Stephen J. Obrey, David J. Devlin, Jose Maria Sansinena
  • Patent number: 8414680
    Abstract: A method or device for controlling the operation of an electrostatic precipitator, ESP, is provided. The ESP is used to remove dust particles from a process gas generated by a combustion process. An indicator signal is generated, typically by a temperature sensor, which signal is indicative of the temperature of combustion air fed to the combustion process. The ESP is operated in a manner depending on the indicator signal. Thereby, back-corona effects may be avoided to a great extent.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: April 9, 2013
    Assignee: ALSTOM Technology Ltd
    Inventor: Anders N. G. Karlsson
  • Patent number: 8177886
    Abstract: A method of continuously removing nitrogen from a blast furnace exhaust stream containing oxygen, nitrogen and unburned hydrocarbons in order to form a supplemental feed to a gas turbine engine containing residual hydrocarbon fuel by first removing entrained solid particulates in the blast furnace exhaust stream to create a substantially particulate-free gas, passing the particulate-free stream through at least one separator bed containing an adsorptive material capable of adsorbing nitrogen from air, adsorbing substantially all of the nitrogen as interstitial nitrogen on solids within the separator bed, feeding non-adsorbed hydrocarbon fuel and oxygen components leaving the separator to a gas turbine engine and removing the adsorbed nitrogen from the separator bed.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: May 15, 2012
    Assignee: General Electric Company
    Inventors: Sam David Draper, Shahryar Rabiei
  • Patent number: 8167986
    Abstract: An airborne particulate sampling device is disclosed. The device includes a conduit whose interior allows the flow of air through the device. The conduit, or at least its surface, is a conductor. The device also includes an electrode with a sharp tip or edge on or near the output side of the conduit. An electrically conducting particle collector outside the conduit is positioned so that a surface is perpendicular or approximately perpendicular to the axis of the funnel. A fan or other blower forces air through the funnel. A power supply imparts an electrostatic potential difference between the electrode, on the one hand, and the holder and particle collector, on the other hand. The electrostatic potential difference produces a corona field in the air in the vicinity of the electrode's sharp tip. The corona field imparts a charge to airborne particles.
    Type: Grant
    Filed: July 21, 2009
    Date of Patent: May 1, 2012
    Assignee: Board of Supervisors of Louisiana State University and Agricultural and Mechanical College
    Inventors: Raymond W. Schneider, Erik Durr
  • Patent number: 8157902
    Abstract: The present invention is broadly directed to non-thermal plasma-based systems for reducing the amount of particulate matter in a gas stream, as well as to methods for using such systems. The present invention is particularly directed to such non-thermal plasma-based particulate matter reduction systems with self-cleaning surfaces. Particularly contemplated are self-cleaning surfaces that reduce particulate matter buildup such as is likely to cause the reduction of non-thermal plasma production in the system, and therefore the ability of such systems to reduce the amount of particulate matter in the gas stream.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: April 17, 2012
    Assignee: Environmental Energy Technologies, Inc.
    Inventors: Ali Ogut, Richard Backus
  • Patent number: 7927401
    Abstract: A device for reducing the number of particles in the exhaust gas of an internal combustion engine includes at least two structures through which an exhaust gas can flow, initially through a first structure and then through a second structure during operation. An electrical potential difference can be generated between the structures. In this way, the exhaust gas downstream of the second structure has fewer particles, averaged over time, than the exhaust gas upstream of the first structure. In addition, the particles downstream of the second structure have a larger mean diameter than those upstream of the first structure, so that it is possible to reduce emissions, in particular of fine dust, in the exhaust gas of internal combustion engines. A method for reducing the number of particles in the exhaust gas of an internal combustion engine, is also provided.
    Type: Grant
    Filed: July 14, 2008
    Date of Patent: April 19, 2011
    Assignee: EMITEC Gesellschaft fuer Emissionstechnologie mbH
    Inventor: Rolf Brück
  • Publication number: 20100326272
    Abstract: Aspects of the invention include a method and apparatus for reversibly sorbing a target gas. In one embodiment, an apparatus for reversibly sorbing a target gas is disclosed. The apparatus includes an inlet, a multi-channel monolith coupled to the inlet, the multi-channel monolith including a plurality of channels, each one of the plurality of channels includes one or more walls, wherein at least one of the one or more walls of at least one of the plurality of channels is porous and wherein one or more of the plurality of channels contain a sorbent and an outlet coupled to the multi-channel monolith.
    Type: Application
    Filed: June 25, 2009
    Publication date: December 30, 2010
    Inventors: MARIANNA F. ASARO, Yigal Blum
  • Publication number: 20100282078
    Abstract: A method of continuously removing nitrogen from a blast furnace exhaust stream containing oxygen, nitrogen and unburned hydrocarbons in order to form a supplemental feed to a gas turbine engine containing residual hydrocarbon fuel by first removing entrained solid particulates in the blast furnace exhaust stream to create a substantially particulate-free gas, passing the particulate-free stream through at least one separator bed containing an adsorptive material capable of adsorbing nitrogen from air, adsorbing substantially all of the nitrogen as interstitial nitrogen on solids within the separator bed, feeding non-adsorbed hydrocarbon fuel and oxygen components leaving the separator to a gas turbine engine and removing the adsorbed nitrogen from the separator bed.
    Type: Application
    Filed: May 7, 2009
    Publication date: November 11, 2010
    Inventors: Sam David Draper, Shahryar Rabiei
  • Patent number: 7828883
    Abstract: A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: November 9, 2010
    Assignee: Lawrence Livermore National Security, LLC
    Inventors: Roger D. Aines, William L. Bourcier
  • Publication number: 20100089234
    Abstract: The present invention relates to a device and method for separating particulate material from a gas flow, comprising a substantially elongate housing provided with a peripheral wall and an inlet opening for admitting the gas flow with particulate material into the housing; a number of electrodes extending in the housing up to a predetermined radial distance from the peripheral wall; and an outlet opening arranged downstream in the housing for discharging the gas flow, wherein the outlet opening extends from the axial centre line of the housing to a point some radial distance from a peripheral wall of the housing, and wherein the particulate material is guided into an intermediate space between the outlet opening and the peripheral wall.
    Type: Application
    Filed: October 11, 2007
    Publication date: April 15, 2010
    Applicant: Virus Free Air B.V.
    Inventor: Eliane Khoury
  • Patent number: 7651548
    Abstract: The frequency of a cyclically varying voltage, (fv), is made equal to or higher than the frequency of a streamer discharge, (fs), thereby making it possible to reduce the discharge delay time which is caused in a single streamer discharge.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: January 26, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Toshio Tanaka, Kenkichi Kagawa, Kanji Motegi
  • Patent number: 7547353
    Abstract: The invention relates to a pulse generating system for generating high voltage pulses to energize an electrostatic precipitator (10), the system including: a first power supply (1) and a second power supply (2), where said second power supply (2) is arranged to pre-charge said electrostatic precipitator (10) to a DC voltage; a storage capacitor (7) and a series inductance; a switching device (5) coupled in parallel with an anti-parallel rectifier device (6); and wherein the system is arranged to be coupled to the electrostatic precipitator. The invention relates to provide such a pulse generating system with enhanced efficiency compared to present pulse generating systems and with enhanced protection of the components of the system in case of sparks in the electrostatic precipitator (10). This is achieved, when the switching device (5) of the system has turn-off capability and when the system includes a clamping circuit (11-13; 60-67).
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: June 16, 2009
    Assignee: F.L. Smidth Airtech A/S
    Inventors: Victor Reyes, Claus Taarning
  • Publication number: 20090056539
    Abstract: An air purifying device including a mounting body configured for connection to a duct or plenum of an air handling system is provided. The mounting body includes a substantially planar surface for removable connection to an ultraviolet illumination device. An aperture is provided through the substantially planar surface of the mounting body for passing an ultraviolet lamp of the ultraviolet illumination device through the mounting body. A low-profile porous substrate including a photocatalyst is connected to and extends from the mounting body. Further provided is a combination air purifying device and ultraviolet illumination device and a method of purifying air within an air handling system.
    Type: Application
    Filed: August 27, 2008
    Publication date: March 5, 2009
    Applicant: AirGorilla Corporation
    Inventor: John R. Garrett
  • Patent number: 7497893
    Abstract: A method for handling a fluid may be incorporated into the operation of, for example, a corona discharge device and an electric power supply. Such a corona discharge device typically includes at least one corona discharge electrode and at least one collector electrode positioned proximate each other so as to provide a total inter-electrode capacitance within a predetermined range. The electric power supply is connected to supply an electric power signal to said corona discharge and collector electrodes so as to cause a corona current to flow between the corona discharge and collector electrodes. A relationship between alternating and direct (or constant, non-time varying) components of the voltage may be expressed as (Vac/Vdc)?(Iac/Idc).
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: March 3, 2009
    Assignee: Kronos Advanced Technologies, Inc.
    Inventor: Igor A. Krichtafovitch
  • Publication number: 20080289494
    Abstract: The invention provides methods and apparatus for a cold arc discharge used to decompose natural gas or methane into its gaseous constituents and carbon in the form of solid particles. The gaseous constituents obtained are mainly hydrogen and acetylene and they are produced in admixture with unreacted natural gas or methane.
    Type: Application
    Filed: February 19, 2008
    Publication date: November 27, 2008
    Inventors: Tobie Jean BOUTOT, Zhuomin Liu, Kenneth Ricky Buckle, Francis Xavier Collins, Charles Andrew Estey, Donald MacFarlane Fraser, Stanley Jaye Claus, Thomas Keith Whidden
  • Patent number: 7419601
    Abstract: Disclosed herein are articles for removing contaminants from a fluid, such as a liquid or gas, the article comprising carbon nanotubes, which comprise at least one molecule or cluster attached thereto or located therein, wherein the carbon nanotubes are present in the article in an amount sufficient to reduce the concentration of contaminants in fluid that come into contact with the article. A method of making the nanomesh material used in such articles is also disclosed, as are methods of purifying fluids using these articles.
    Type: Grant
    Filed: April 22, 2005
    Date of Patent: September 2, 2008
    Assignee: Seldon Technologies, LLC
    Inventors: Christopher H. Cooper, Alan G. Cummings, Mikhail Y. Starostin, Charles P. Honsinger
  • Publication number: 20080178737
    Abstract: An electrostatic precipitator element comprises preferably a mesh made of at least two individually insulated conductors with defined openings therebetween. An electrical field in the openings electrostatically attracts suspended particulate to a respective conductors for collection.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 31, 2008
    Applicant: PRATT & WHITNEY CANADA CORP.
    Inventor: Kevin Allan DOOLEY
  • Patent number: 7377957
    Abstract: A method of utilizing a filter having a filter body removing solid particles from a fluid, in order to extend the life cycle of the filter body before cleaning or replacement thereof is required, characterized in applying to the fluid, upstream of the filter body, an AC electrical field of a frequency and intensity to agglomerate solid particles in the fluid reaching the filter body, such as to reduce the number of smaller particles in the fluid tending to clog the filter body. Also described are a plurality of filter constructions for extending the life cycle of the filter body in accordance with the above method.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: May 27, 2008
    Assignees: Innovative Defense Technologies Ltd.
    Inventor: Gideon Rosenberg
  • Patent number: 7364606
    Abstract: Provided are a hollow inner electrode constituted by an electrically conductive filter capable of capturing particulates, a cylindrical outer electrode circumferentially surrounding the electrode, a housing incorporated in a flow passage of exhaust and accommodating the electrodes and, a temperature sensor for detecting temperature of the exhaust and an electric discharge controller for controlling electric power to be distributed to the electrodes and on the basis of a detected value of the temperature sensor. When the temperature of the exhaust obtained by the temperature sensor is lowered, electric power necessary for generation of discharge plasma is distributed by the discharge controller to the electrodes and, thereby oxidizing the particulates captured by the electrode to reduce electricity consumption.
    Type: Grant
    Filed: June 2, 2004
    Date of Patent: April 29, 2008
    Assignee: Hino Motors, Ltd.
    Inventors: Masatoshi Shimoda, Koichi Machida, Takatoshi Furukawa
  • Patent number: 7300493
    Abstract: Disclosed is an apparatus and method for controlling an air cleaning. The apparatus includes an air cleaning element, an AC high-voltage generator and a control unit. The air cleaning element generates negative ions and ozone using plasma discharge, and cleans indoor air using the negative ions and ozone. The AC high-voltage generator generates an AC high-voltage, and applies the AC high-voltage to the air cleaning element. The control unit varies at least one of the AC voltage and AC frequency applied to the air cleaning element by the AC high-voltage generator depending on a state of indoor air being cleaned using the air cleaning element. Therefore, it is possible to effectively generate negative ions while minimizing ozone generation to an acceptable level depending on a state of indoor air, thereby increasing air cleaning performance so as to sterilize and clean contaminants more efficiently.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: November 27, 2007
    Assignee: LG Electronics Inc.
    Inventors: Ho Jung Kim, In Ho Choi, Kwan Ho Yum, Ho Seon Choi
  • Patent number: 7285155
    Abstract: The present invention provides an air treatment device including a housing, an emitter electrode configured within the housing and a collector electrode configured within the housing and positioned downstream from the emitter electrode. The device preferably increases the ions produced for a start up period after the device is initially turned on, wherein the device automatically decreases ion production after the desired period. The device preferably includes a first and second voltage source to selectively increase and decrease voltages applied to the emitter and/or collector electrode to adjust the ion production. In one embodiment, the device includes a voltage controller to selectively adjust the voltage provided by the voltage source for the start up period and normal operation.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: October 23, 2007
    Inventors: Charles E. Taylor, Andrew J. Parker, Igor Y. Botvinnik, Shek Fai Lau, Gregory S. Snyder, John Paul Reeves
  • Patent number: 7175695
    Abstract: Disclosed is a filtration enhancement apparatus and an associated method. The apparatus includes a number of electromagnetic grids that are placed in series. The first grid conditions ambient particles to generate particles with both a positive and a negative charge. These charged particles are then delivered to a second and third grid wherein a low, medium, and/or high frequency alternating current is employed to force the positive and negative charged particles to collide and conglomerate with one another. The conglomerated particles are then sent into the ambient environment for subsequent filtration.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: February 13, 2007
    Inventor: Don H. Hess
  • Patent number: 7081152
    Abstract: A gas separation apparatus which uses electrostatic precipitators and a DC power supply is controlled to optimally remove moderate to high resistivity ash. The DC power supply is pulse width modulated to maximize the product of the peak electric field and the average electric field. The method used to optimize operation includes selecting initial on and off times for the power supply, operating the power supply using the initial off and on times, and progressively decreasing the off time. A determination is made whether the off time may be further decreased. Ultimately, the on and off time intervals that produce the highest peak and average voltage are determined, and the system is operated using these parameters. A procedure may be periodically repeated to monitor the process and detect if there has been a change in the system that would require new time intervals.
    Type: Grant
    Filed: February 18, 2004
    Date of Patent: July 25, 2006
    Assignee: Electric Power Research Institute Incorporated
    Inventors: Ralph F. Altman, Robert N. Guenther
  • Patent number: 6611440
    Abstract: An apparatus and method for controlling voltage applied to an electrostatic precipitator is disclosed. This apparatus includes a pulsating, direct current, voltage mechanism that is operable to receive power from a single phase, alternating current voltage source, and a spiral wound filter capacitor, wherein the pulsating, direct current, voltage mechanism is electrically connected in parallel to the spiral wound filter capacitor and the spiral wound filter capacitor is electrically connected in parallel to the electrostatic precipitator. Optionally, a resistor is present to lower the transient voltage rating of the spiral wound filter capacitor. A switching mechanism may be utilized to apply differing amounts of capacitance and inductance in order to apply a range of voltage waveforms to the electrostatic precipitator to potentially maximize particulate collection efficiency for the electrostatic precipitator.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: August 26, 2003
    Assignee: BHA Group Holdings, Inc.
    Inventors: David F. Johnston, Michael M. Mahler, Terry L. Farmer, Robert Edgar Hummell, III
  • Patent number: 6461405
    Abstract: A method of operating an electrostatic precipitator (7) includes feeding the precipitator with electric power generated by a power supply (10) according to a regime adapted to impart between the precipitator electrodes a voltage having a DC component and an AC component. A control unit (8) measures the electrode voltage, establishes a voltage peak value and a voltage mean value, and computes the product of peak value by mean value to arrive at an index of expected performance (IEP). Operating set points are tuned so as to maximize this index of expected performance.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: October 8, 2002
    Assignee: F.L. Smidth Airtech A/S
    Inventor: Victor Reyes
  • Patent number: 6224653
    Abstract: An electrical apparatus includes a reaction chamber. A stream of contaminated gasses flows through the chamber. An elongated coronating electrode is positioned in the reaction chamber for producing a corona discharge within the chamber. A multi-stage Fitch generator connected to the electrode produces a high level, rapidly pulsating voltage in the electrode. Controlled amounts of an inert gas or inert gas-air mixture are combined with the contaminated gases to provide a high concentration of inert gas in the reaction chamber. In the inert gas-enriched atmosphere, the pulsating corona discharge produces a high concentration of metastable intermediates that greatly increase the rate of chemical conversion of the contaminants. Switching circuitry allows the pulsating voltage output of the Fitch generator to be superimposed on a constant direct current voltage in the electrode, setting up an electrostatic field in the reaction chamber for removing conversion byproducts from the gas stream.
    Type: Grant
    Filed: December 29, 1998
    Date of Patent: May 1, 2001
    Assignee: Pulsatron Technology Corporation
    Inventors: Adolf Pavlovich Shvedchikov, Aleksander Zalmanovich Ponizovsky, Lazar Zalmanovich Ponizovsky, Sergei Petrovich Kryutchkov, Vladimir Yakovlevich Starobinsky
  • Patent number: 6063168
    Abstract: An apparatus for charging an electrostatic precipitator, powered by a power supply and having a plurality of corona electrodes and a plurality of collector electrodes, such that a precipitator capacitance may be formed therebetween, includes a storage capacitor across the power supply, having a storage capacitance. A voltage switch is capable of selectively electrically coupling the electrostatic precipitator to the storage capacitor. The storage capacitance is sufficient to charge the electrostatic precipitator to a preselected operative voltage within a rise time greater than a first preselected value and less than a second preselected value.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: May 16, 2000
    Assignee: Southern Company Services
    Inventors: Grady B. Nichols, Sabert Oglesby, Jr.
  • Patent number: 5972076
    Abstract: A method for charging an electrostatic precipitator, powered by a power supply and having a plurality of corona electrodes and a plurality of collector electrodes, such that a precipitator capacitance may be formed therebetween, includes a storage capacitor across the power supply, having a storage capacitance. A voltage switch is capable of selectively electrically coupling the electrostatic precipitator to the storage capacitor. The storage capacitance is sufficient to charge the electrostatic precipitator to a preselected operative voltage within a rise time greater than a first preselected value and less than a second preselected value.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: October 26, 1999
    Inventors: Grady B. Nichols, Sabert M Oglesby, Jr.
  • Patent number: 5827407
    Abstract: An indoor air pollutant destruction apparatus destroys pollutants by a corona discharge that is generated by a rapidly oscillating electric field. Free electrons generated by the corona discharge produces ozone (O.sub.3), which effectively destroys volatile organic compounds (VOCs) and biological forms such as bacteria, fungi, viruses and spores. Fine particulate materials such as smoke and dust are charged by the corona discharge, and when they pass through the rapidly oscillating electric field, they coagulate to form larger particles which are then filtered out.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: October 27, 1998
    Assignee: Raytheon Company
    Inventors: John H. S. Wang, Weldon S. Williamson, Nelson William Sorbo
  • Patent number: 5707422
    Abstract: A method for use in an electrostatic precipitator unit, of controlling, with a view to cleaning an incoming dust-laden gas, the supply of conditioning agent to the incoming contaminated gas upstream of the precipitator unit. The precipitator unit includes discharge electrodes and collecting electrodes, between which a varying high voltage is maintained by means of a pulsating direct current supplied thereto. The frequency, the pulse charge and/or pulse length of the pulsating direct current are so varied that a plurality of frequency-charge-length combinations are obtained. For each combination, a figure of merit is measured or calculated. The figures of merit are used for establishing an optimal combination. The supply of conditioning agent is adjusted in dependence upon the pulse frequency of the established optimal combination.
    Type: Grant
    Filed: October 12, 1995
    Date of Patent: January 13, 1998
    Assignee: ABB Flakt AB
    Inventors: Hans Jacobsson, Kjell Porle
  • Patent number: 5639294
    Abstract: Method for controlling, in case of flashover between electrodes in an electrostatic precipitator, the current supply to the electrodes from a controllable high-voltage direct-current source. The current supplied to the precipitator and the voltage between the electrodes of the precipitator are measured substantially continuously or at close intervals. After the flashover, the current supply to the electrodes of the precipitator is completely interrupted during a first time interval. During a second time interval directly following the first time interval, a current which is greater that the one supplied immediately before the flashover is supplied to the precipitator. Subsequently, the current is reduced to a value below the one prevailing immediately before the flashover.
    Type: Grant
    Filed: September 19, 1995
    Date of Patent: June 17, 1997
    Assignee: ABB Flakt AB
    Inventor: Per Ranstad
  • Patent number: 5601633
    Abstract: Electrical method for removing ecologically noxious substances from gases which includes an electrical precipitator having a reaction chamber through which a stream of the gases to be cleaned passes, and which includes an elongated electrode extending into said reaction chamber for producing a corona discharge within the chamber. The method of the invention includes a multi-stage Fitch generator connected to the electrode which produces a high level pulsating voltage superimposed on a constant direct current voltage. The pulsating voltage causes the electrode to produce the corona effect in the chamber, and the constant direct current voltage sets up an electrostatic field which removes unwanted products of the corona discharge from the gas stream passing through the chamber. The Fitch generator is adapted to provide pulsating voltages of sufficient amplitude and steepness to produce a high density, high energy corona discharge within the chamber.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: February 11, 1997
    Inventors: Lazar Z. Ponizovsky, Aleksander Z. Ponizovsky, Viktor A. Potapov, Adolf P. Shvedchikov
  • Patent number: 5597403
    Abstract: A system for preconditioning flue gas to be treated in an electrostatic precipitator having a set of electrostatic elements and a power supply, which supplies an intermittent power to the electrostatic elements, includes a source of a conditioning agent, and a current sensor and a voltage sensor for detecting the half-cycle current and voltage supplied to the electrostatic elements. The system also includes a power measuring circuit, responsive to the current sensor and to the voltage sensor, which develops an indication of the power supplied to the electrostatic elements and a controller, responsive to the power indication, which controls the amount of conditioning agent added to the flue gas in order to maintain the power at a substantially predetermined level.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: January 28, 1997
    Assignee: The Chemithon Corporation
    Inventor: William G. Hankins
  • Patent number: 5591249
    Abstract: A method is used for preconditioning flue gas to be treated in an electrostatic precipitator having a set of electrostatic elements which are intermittently energized by a power supply. The method uses a current sensor and a voltage sensor to detect the current and the voltage supplied to the electrostatic elements during an energized half-cycle of the power delivered to the electrostatic precipitator and develops an indication of the intermittent power supplied to the electrostatic elements from the current and voltage sensor measurements. The amount of a conditioning agent added to the flue gas is controlled to maintain the power indication at a substantially predetermined level.
    Type: Grant
    Filed: March 22, 1996
    Date of Patent: January 7, 1997
    Assignee: The Chemithon Corporation
    Inventor: William G. Hankins
  • Patent number: 5575836
    Abstract: There is provided a capacitor having an end connected to the ground and the other end connected through a secondary winding of a pulse transformer to the discharge electrode. The ground side terminal of the capacitor is connected through a smoothing circuit to a positive voltage side output terminal of a base power supply circuit and a negative voltage side terminal of the base power supply circuit is connected to the discharge electrode side terminal of the capacitor. An output terminal of a pulse power supply circuit is connected to a primary winding of the pulse transformer. The base voltage and the pulse voltage can be controlled independently, and it becomes possible to apply a steep pulse with large output power to the discharge electrode.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: November 19, 1996
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Sakao Sugiura, Osamu Kawabata, Nobuo Teramura
  • Patent number: 5556448
    Abstract: An improved electrostatic precipitator system is provided for use in high-grease atmospheres in which the grease is electrically conductive. The precipitator includes high-voltage insulators that are both located in areas unlikely to accumulate electrically-conductive grease and that, in themselves, can operate in a high-voltage system without tracking, even when a certain amount of conductive grease has accumulated on the insulators' surfaces. In a multi-cell precipitator system, a high-voltage insulator is provided as part of a cell-to-cell assembly that receives high-voltage electricity on one side of its insulator, and conducts that electricity to its opposite side, and is placed in a specially-shaped cut-out in the bulkhead between the cell chambers, in which the cut-out is shaped so as to minimize the amount of grease that may accumulate upon the cell-to-cell assembly's insulators.
    Type: Grant
    Filed: January 10, 1995
    Date of Patent: September 17, 1996
    Assignee: United Air Specialists, Inc.
    Inventors: William A. Cheney, John T. Grady, Jr., Victor L. Sellers, Kevin Lefler, Robert S. Wilks
  • Patent number: 5542967
    Abstract: Electrical apparatus for removing ecologically noxious substances from gases which includes an electrical precipitator having a reaction chamber through which a stream of the gases to be cleaned passes, and which includes an elongated electrode extending into said reaction chamber for producing a corona discharge within the chamber. The apparatus of the invention includes a multi-stage Fitch generator connected to the electrode which produces a high level pulsating voltage superimposed on a constant direct current voltage. The pulsating voltage causes the electrode to produce the corona effect in the chamber, and the constant direct current voltage sets up an electrostatic field which removes unwanted products of the corona discharge from the gas stream passing through the chamber. The Fitch generator is adapted to provide pulsating voltages of sufficient amplitude and steepness to produce a high density, high energy corona discharge within the chamber.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: August 6, 1996
    Inventors: Lazar Z. Ponizovsky, Aleksander Z. Ponizovsky, Viktor A. Potapov, Adolf P. Shvedchikov
  • Patent number: 5241449
    Abstract: A radon decay product remover for use in a conventional, residential lamp. The remover screws into the light bulb socket of a lamp and provides a replacement socket for a light bulb. The flow of electric current to the light bulb is controlled by an on-off switch in the radon decay product remover. When used in a table lamp, an ion generator includes electrodes (from which negative and/or positive ions are emitted) that attach to the exterior of the lamp shade.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: August 31, 1993
    Inventors: Dade W. Moeller, Stephen N. Rudnick