Patents by Inventor Pramodh Nijhawan

Pramodh Nijhawan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230158449
    Abstract: Described herein is a dry sorbent injection system and process for removing sulfur oxides from a flue gas. The process generally comprises treating the flue gas with a dry sorbent material to convert the sulfur oxides to sodium sulfate particulates. The sodium sulfate particulates may then be introduced into a mix tank with water to form sodium sulfate solution. The sodium sulfate solution may then be reacted with a calcium hydroxide slurry to produce a reaction mixture comprising calcium sulfate precipitate and a sodium hydroxide solution. The calcium sulfate (gypsum) may be recovered, and the sodium hydroxide solution may be recirculated to pre-treat the flue gas by removing at least a portion of the sulfur dioxide and/or cooling the flue gas stream.
    Type: Application
    Filed: November 18, 2022
    Publication date: May 25, 2023
    Applicant: Industrial Accessories Company
    Inventor: Pramodh Nijhawan
  • Patent number: 8695516
    Abstract: The present invention provides improved boiler assemblies (10) with enhanced pollution abatement properties through injection and recycling of particulate sorbent materials including sodium bicarbonate, trona, and mixtures thereof. The assemblies (10) include a boiler (12), economizer (14), air heater (15), and recirculation reactor (16). Fresh sorbent material is introduced via assembly (60) into the boiler assembly (10) at one or more injection locations, and serves to sorb NOx, SOx, and other pollutants in the flue gas. The flue gas and entrained sorbent material then pass through reactor (16) for separation of sorbent, which is then recycled for injection back into the assembly (10) upstream of reactor (16). In another aspect, the invention provides pollution abatement apparatus (110) and methods employing an upstream recirculation reactor (114), a supply of fresh sorbent (118), and a downstream collector (116).
    Type: Grant
    Filed: August 20, 2011
    Date of Patent: April 15, 2014
    Assignee: Industrial Accessories Company
    Inventor: Pramodh Nijhawan
  • Publication number: 20110303133
    Abstract: The present invention provides improved boiler assemblies (10) with enhanced pollution abatement properties through injection and recycling of particulate sorbent materials including sodium bicarbonate, trona, and mixtures thereof. The assemblies (10) include a boiler (12), economizer (14), air heater (15), and recirculation reactor (16). Fresh sorbent material is introduced via assembly (60) into the boiler assembly (10) at one or more injection locations, and serves to sorb NOX, SOX, and other pollutants in the flue gas. The flue gas and entrained sorbent material then pass through reactor (16) for separation of sorbent, which is then recycled for injection back into the assembly (10) upstream of reactor (16). In another aspect, the invention provides pollution abatement apparatus (110) and methods employing an upstream recirculation reactor (114), a supply of fresh sorbent (118), and a downstream collector (116).
    Type: Application
    Filed: August 20, 2011
    Publication date: December 15, 2011
    Applicant: INDUSTRIAL ACCESSORIES COMPANY
    Inventor: Pramodh Nijhawan
  • Publication number: 20100263577
    Abstract: The present invention provides improved boiler assemblies (10) with enhanced pollution abatement properties through injection and recycling of particulate sorbent materials including sodium bicarbonate, trona, and mixtures thereof. The assemblies (10) include a boiler (12), economizer (14), air heater (15), and recirculation reactor (16). Fresh sorbent material is introduced via assembly (60) into the boiler assembly (10) at one or more injection locations, and serves to sorb NOx, SOx, and other pollutants in the flue gas. The flue gas and entrained sorbent material then pass through reactor (16) for separation of sorbent, which is then recycled for injection back into the assembly (10) upstream of reactor (16). The present invention can also be used in industrial applications where the same emissions are generated and are needed to be controlled. Examples of such applications are Cement and Lime Kilns.
    Type: Application
    Filed: April 21, 2009
    Publication date: October 21, 2010
    Applicant: Industrial Accessories Company
    Inventor: Pramodh Nijhawan
  • Patent number: 4477910
    Abstract: A fumes control system for use with a furnace having a top-chargeable furnace vessel mounted on a first support with means for charging the furnace adjacent to the vessel and means for collecting the melt from the furnace adapted to overlie a second support defining a tapping site adjacent to the furnace vessel. The fumes control system comprises a housing covering the top and sides of the furnace in sealing engagement with the first and second supports and is adapted to entirely enclose the furnace and collecting means. The fumes control system further comprises exhaust means with dampers associated therewith, which dampers are interconnected via control means to selectively exhaust fumes generated during charging, melting/refining and tapping operations at the respective sites.
    Type: Grant
    Filed: April 7, 1983
    Date of Patent: October 16, 1984
    Assignee: The Bahnson Company
    Inventors: Pramodh Nijhawan, Eugene D. Schaltenbrand
  • Patent number: 4435197
    Abstract: A baghouse filter having a filter chamber separated by a partition between the clean gas side and the dirty gas side. The partition has a plurality of apertures, in each of which is mounted a filter unit for removal and replacement. The housing has an access opening to permit access to the interior of the housing and the opening is sufficiently large to permit withdrawal of the partition from the housing through the opening so as to permit replacement of the filter units exteriorly of the housing. In the present instance, the partition of the housing is mounted on a door closing the access opening, so that the displacement of the access door from the housing automatically displaces the partition from the housing to permit removal and replacement of the filter units. The filter unit assemblies permit mounting of the filter units from the dirty gas side of the partition with suitable sealing to prevent unfiltered gaseous medium from bypassing of the filter units.
    Type: Grant
    Filed: April 9, 1982
    Date of Patent: March 6, 1984
    Assignee: The Bahnson Company
    Inventors: Pramodh Nijhawan, William W. Avera
  • Patent number: 4356064
    Abstract: A fumes control system duct-and-car arrangement for a duct including a wall portion closed by a flexible web, and a support structure in the duct under the web to prevent collapse of the web into the duct under evacuation includes a car disposed for movement along the duct to raise the web and couple the interior of the car to the interior of the duct. The car is provided with a door which can be opened to gain access to the interior of the car. The support structure for the web provides an access way so that maintenance and inspection personnel can move from the interior of the car into the interior of the duct. Various types of apparatus for moving the car along the duct include a motor mounted on the car and a wheel supporting the car from the duct and driven by the motor. Another motive mechanism provides a motor mounted beyond one of the limits of travel of the car along the duct, and a flexible cable, chain or the like, pulled by actuation of the motor to move the car along the duct.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: October 26, 1982
    Assignee: The Bahnson Company
    Inventors: Pramodh Nijhawan, Joseph M. Duckworth
  • Patent number: 4257849
    Abstract: A coke guide fumes control system includes a hood overlying a coke guide and apparatus for continuously evacuating the hood during a coke pushing operation. Several types of apparatus are illustrated. Some types are self-contained, including blowers and filter mechanisms mounted on the coke guide hood. The fumes and dusts from the pushing operation are evacuated through the filter mechanism under suction established by the blower, and the purified air pulled through the blower is exhausted to atmosphere. Alternatively, the hood can include slot-like nozzles cooperating with the blower to generate an air curtain which is directed down the sides of the coke guide to prevent the escape of contaminants through openings typically provided in the sides of such coke guide.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: March 24, 1981
    Assignee: Envirotech Corporation
    Inventors: Pramodh Nijhawan, Joseph M. Duckworth
  • Patent number: 4247370
    Abstract: A coke oven fumes control system includes a duct-and-car arrangement extending alongside the coke oven quench car track. The car of the duct-and-car system supports a hood movable into overlying relation with a selected portion of the quench car. An additional hood overlies the coke guide. A system of connecting ducts connects the coke guide hood through the quench car hood to the car of the duct-and-car arrangement, thereby providing evacuation of both the quench car hood and the coke guide hood. The quench car hood is divided into a plurality of sectors. Butterfly valve dampers are provided for controlling evacuation of the various sectors of the quench car hood, as well as the coke guide hood.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: January 27, 1981
    Assignee: Envirotech Corporation
    Inventors: Pramodh Nijhawan, Joseph M. Duckworth
  • Patent number: 4089640
    Abstract: A hood for capturing fumes and dust generated during operating of a metal melting furnace including an integral conveyor for charging the furnace. The furnace has an upwardly opening mouth covered by a lid. The hood overlies the lid to capture fumes and dust emanating from the furnace during melting, slagging, pouring, and associated furnace operations. An opening is provided in the hood for insertion of material, e.g., scrap metal, into the furnace. The instant invention includes a conveyor flexibly, e.g., pivotally, mounted between the hood and the lid. The hood opening includes a hopper mounted above the conveyor and opening through the hood into the conveyor. The illustrated system further includes an opening through the furnace lid and a chute adjacent the furnace lid opening for engaging a distal end of the conveyor when the conveyor is moved into a use position. A door is provided to close the distal end of the conveyor when the conveyor is not moving material into the furnace.
    Type: Grant
    Filed: November 29, 1976
    Date of Patent: May 16, 1978
    Assignee: Hawley Manufacturing Corporation
    Inventors: Robert C. Overmyer, Pramodh Nijhawan
  • Patent number: 3999001
    Abstract: An exhaust system for use with an electric arc melting furnace having a crucible and an upwardly directed mouth covered by a roof, and a device coupled to the roof for projecting it upwardly along an axis and pivotally about the axis to a position out of registry with the mouth for providing access for charging the furnace, and a device for tilting the furnace for tapping and slagging. In one embodiment the fumes exhaust system comprises an exhaust fan, a telescoping main fumes exhaust duct flexibly coupled at one end to the exhaust fan, a coupler flexibly connected to the other end of the main fumes exhaust duct and a tapping and melting manifold and hood flexibly and telescopically connected to the coupler. The tapping and melting manifold and hood are connected to the roof and project vertically along the roof axis and pivot about the roof axis with the roof to a position out of registry with the mouth. A slagging manifold and hood are mounted on the furnace and connected to the coupler.
    Type: Grant
    Filed: March 8, 1976
    Date of Patent: December 21, 1976
    Assignee: Hawley Manufacturing Corporation
    Inventors: Robert C. Overmyer, Pramodh Nijhawan
  • Patent number: 3979551
    Abstract: For use with an electric arc melting furnace having a crucible and an upwardly directed mouth covered by a roof, and a device coupled to the roof for projecting it upwardly along an axis and pivotally about the axis to a position out of registry with the mouth for providing access for charging the furnace, and a device for tilting the furnace for tapping and slagging, a fumes exhaust system comprising an exhaust fan, a telescoping main fumes exhaust duct flexibly coupled at one end to the exhaust fan, a coupler flexibly connected to the other end of the main fumes exhaust duct and a tapping and melting manifold and hood flexibly and telescopically connected to the coupler. The tapping and melting manifold and hood are connected to the roof and project vertically along the roof axis and pivot about the roof axis with the roof to a position out of registry with the mouth. A slagging manifold and hood are mounted on the furnace and connected to the coupler.
    Type: Grant
    Filed: September 24, 1975
    Date of Patent: September 7, 1976
    Assignee: Hawley Manufacturing Corporation
    Inventors: Robert C. Overmyer, Pramodh Nijhawan