Patents Assigned to Dravo Corporation
  • Patent number: 4779992
    Abstract: A slaker includes a substantially straight, circular sidewall, a substantially flat bottom, and a top. A solid and a liquid feed inlet are disposed at the top of the vessel and an outlet is disposed at the bottom of the vessel. Apparatus is provided for mixing the solid and the liquid within the vessel at high speed and separate apparatus is provided for sweeping the bottom and sidewall of the vessel at low speed. The mixing apparatus and the sweeping apparatus apply substantially only horizontal forces to the solid and the liquid being mixed within the vessel. The slaker further includes apparatus for recirculating at least a portion of the solid and the liquid being mixed within the vessel which flows through the outlet and apparatus for discharging the resultant mixed solid and liquid from the slaker.
    Type: Grant
    Filed: June 3, 1987
    Date of Patent: October 25, 1988
    Assignee: Dravo Corporation
    Inventor: David T. Underwood
  • Patent number: 4760968
    Abstract: An integrated dust containment system for machines such as rotary crusher/breakers, vibratory screens and the like of the type use in sizing dusty bulk materials, such as for coal, ore and the like. A substantially airtight enclosure having integral air filter means and fan means is detachably fitted to the machine housing adjacent the material treating station such that the air filter means is in communication with the dust generation area of the machine. A negative draft generated by the fan means draws in dust laden air from inlet and discharge zones of the machine, as well as from the material treating station for capture of the dust in the filter means and susequent discharge of clean, filtered air from the fan means. Pulsed, compressed air back flushing of the filter means cleans the filters and returns the collected dust cake to the machine interior for subsequent recovery.
    Type: Grant
    Filed: June 30, 1987
    Date of Patent: August 2, 1988
    Assignee: Dravo Corporation
    Inventor: Willard Binzen
  • Patent number: 4714097
    Abstract: A method and apparatus for the containment of dust within a bulk cargo container such as a ship or barge hold. A horizontal stream of ambient air is directed across the hatch opening by a plurality of interconnected air curtain modules which captures fugitive dust along its path. A plurality of interconnected dust collector modules withdraw the entrained dust particles at an opposite side of the hatch opening and exhaust the filtered air stream therefrom and deposit the filter cake back into the hold. The clean exhaust air from the dust collector modules may be used to form a vertical air curtain to deflect crosswinds.
    Type: Grant
    Filed: October 14, 1986
    Date of Patent: December 22, 1987
    Assignee: Dravo Corporation
    Inventors: Willard Binzen, Robert S. Catan
  • Patent number: 4699187
    Abstract: A bulk material receiving hopper is provided with a dust containment system which includes sloped shield plates positioned adjacent a top portion of the hopper to effectively close-off substantially all of the open space thereacross. Restricted material openings are defined by the shield plates and an isolated, dust containment region is established therebeneath to trap the displaced air and entrained fugitive dust generated during a dumping operation. One or more dust collector units communicate with the isolated dust containment region to draw in the displaced air and entrained dust particles.
    Type: Grant
    Filed: October 23, 1986
    Date of Patent: October 13, 1987
    Assignee: Dravo Corporation
    Inventor: Willard Binzen
  • Patent number: 4689007
    Abstract: The thermal treatment is effected in that hot gases are passed through the charge bed. Hot gases are passed downwardly through the charge bed in heat treating zone, oxygen-containing cooling gases are passed upwardly through the charge bed in a cooling zone, and the cooling gases which have been heated are conducted under a continuous gas hood from the cooling zone into the heat treating zone.
    Type: Grant
    Filed: September 4, 1985
    Date of Patent: August 25, 1987
    Assignee: Dravo Corporation
    Inventor: Alois Kilian
  • Patent number: 4683029
    Abstract: A circular solvent extractor useful in a commercial process for the removal of bitumen from tar or oil sands or other solvent extraction processes requiring high tonnage throughput. The extractor comprises two major segments that are stationary, namely, a ring-shaped roof member and a ring-shaped drain trough means positioned therebeneath, and one segment that is movable which comprises a pair of continuous, spaced-apart sidewalls having a plurality of spaced-apart, liquid permeable, process cells rotatably attached to the sidewalls. The sidewalls and their attached process cells are movable about a circular trackway for travel between the fixed hood and drain trough means, forming an annular process chamber therearound. The annular chamber is sealed by upper and lower, circumferential liquid seals coacting between the moving sidewalls and the stationary hood and drain trough means to prevent the leakage of solvent vapors therefrom.
    Type: Grant
    Filed: September 20, 1985
    Date of Patent: July 28, 1987
    Assignee: Dravo Corporation
    Inventors: John F. Oyler, Jerry D. Brand, Richard Zavada
  • Patent number: 4655401
    Abstract: A lump breaker apparatus for a rotary car dumper includes a porous barrier means in the form of a grizzly element, having sized openings therein and positioned in the flow path of the discharged bulk material prior to its entry into the hopper pit. Motorized impact means, preferably rotatable drum means, having a plurality of outwardly protruding striking elements, is mounted on the frame of the rotary dumper, extending between the end plates thereof and moveable with the frame. The impact means is selectively activated to engage and breakup lumps of oversized bulk material retained on the grizzly during a dumping cycle.
    Type: Grant
    Filed: August 22, 1985
    Date of Patent: April 7, 1987
    Assignee: Dravo Corporation
    Inventors: Willard Binzen, Samuel P. Insana, Edward T. Manning, Jr., Cornel Muhoray
  • Patent number: 4626418
    Abstract: A process for the removal of SO.sub.2 from a gaseous mixture containing SO.sub.2 which comprises contacting said gaseous mixture containing SO.sub.2 with a mixture containing a sugar and at least one alkaline earth compound selected from the group consisting of calcium and magnesium carbonates, oxides and hydroxides.
    Type: Grant
    Filed: September 26, 1985
    Date of Patent: December 2, 1986
    Assignee: Dravo Corporation
    Inventors: John W. College, Joseph Vlnaty
  • Patent number: 4609321
    Abstract: The dust collection units in a rotary railroad car dumper installation are mounted over the hopper pit along one or both sides of the cylindrical, rotatable dumper frame so that dust ladened air can be sucked directly into the dust collection units without the need for duct work and the collected dust can be returned directly to the pit without the need for easily clogged screw conveyors and small chutes. A fixed enclosure means encloses the top and sides of the dumper frame and form with air shields mounted on the cylindrical dumper frame, a rotary valve which restricts flow such that ambient air is sucked into the hopper pit by the duct collection units at velocities which exceed the capture velocity of the dust clouds created by dumping of the contents of the car.
    Type: Grant
    Filed: October 29, 1984
    Date of Patent: September 2, 1986
    Assignee: Dravo Corporation
    Inventor: Willard Binzen
  • Patent number: 4603225
    Abstract: A process for separating dimethyl ether from a hydrocarbon mixture which comprises contacting the hydrocarbon mixture with an aqueous solution containing a polar oxygenated hydrocarbon having a polarity of about 1.4 to about 2.0 Debyes.
    Type: Grant
    Filed: September 11, 1985
    Date of Patent: July 29, 1986
    Assignee: Dravo Corporation
    Inventors: James Colaianne, Thomas J. Junker, Lawrence Saroff
  • Patent number: 4575055
    Abstract: A circular traveling grate machine includes rotatable, inner and outer, rail mounted, side frame members forming the sidewalls of an annular hearth region therebetween. A plurality of individually tiltable pallets are positioned in the hearth region and are movable with the side frames along a circular pallet trackway which is positioned within the inner and outer rails of the side frames. A stationary hood is mounted above the hearth region carrying sealing flanges at its lateral edges which extend downwardly in a pair of liquid troughs carried by the rotatable side frames. A stationary windbox is situated below the pallets and is also sealed off by way of lower liquid seals coacting with the side frames. The pallets carry a pair of rotatable hanger brackets at the leading ends thereof which are latched to the undersides of the inner and outer side frames.
    Type: Grant
    Filed: July 15, 1985
    Date of Patent: March 11, 1986
    Assignee: Dravo Corporation
    Inventor: Stanley M. Coulter
  • Patent number: 4573637
    Abstract: Discrete volumes, or slugs, of liquid are accelerated to high velocities utilizing energy stored by compressing the liquid. Liquid is forced into a pressure vessel already filled with liquid to effect the compression. A slug of liquid is ejected from the pressure vessel into a cumulation nozzle by the energy stored in the compressed liquid when a valve is rapidly opened. The valve is opened when an opening force, generated by the compressed liquid, exceeds a closing bias. By repetitively introducing highly pressurized liquid into the pressure vessel, the valve automatically cycles to generate a series of pulsed liquid jets. Rapid opening of the valve is aided by an extension on the valve member which sealingly slides inside the passage of the cumulation nozzle to block release of liquid until the valve member accelerates sufficiently that the required opening rate is achieved as the extension clears the nozzle passage.
    Type: Grant
    Filed: December 6, 1982
    Date of Patent: March 4, 1986
    Assignee: Dravo Corporation
    Inventors: Larry L. Pater, Aubrey C. Briggs
  • Patent number: 4572484
    Abstract: A pallet construction for use in a circular traveling grate machine of the type having rotatable inner and outer side frames which move with the pallets on either side thereof. Various restraining and float means associated with the pallet hanger brackets and their respective axles, as well as with one of the pallet wheels and its respective axle, restrain and permit relative movement of the pallet axles in given radial and circumferential directions, whereby forces and moments are transmitted by the pallets as they mechanically couple the inner and outer side frames. The aforesaid restraining and float means also accommodate the differentials in thermal expansion and contraction between the pallets and the cooler side frames of the traveling grate. The first axles and hanger brackets include spherical antifriction means which permits the pallets to rotatably tilt during the burden discharge operation in situations where the first axles are axially misaligned due to thermal sagging.
    Type: Grant
    Filed: July 15, 1985
    Date of Patent: February 25, 1986
    Assignee: Dravo Corporation
    Inventor: Stanley M. Coulter
  • Patent number: 4563195
    Abstract: Coal tar resulting from the gasification of coal in an industrial gas producer, instead of being discarded as waste, is condensed from the hot fuel gas by a mist-like spray of water to produce a fog-like suspension of tar mixed with the fuel gas. This mixture flows to an electric precipitator where the tar is precipitated and the fuel gas and water vapor are conducted to a mixer while the tar, which has been condensed, is supplied to a tar burner where it is burned either with a stoichiometric volume of air, or less than a stoichiometric volume. The product gases from the tar burner are conducted and discharged hot into the mixer where they supply sensible heat to fuel gas and water vapor and raise the temperature of the mixture above the dew point of the tar remaining in the fuel gas, and from which the hot mixture produced is delivered to a fuel burner or gas consuming apparatus.
    Type: Grant
    Filed: November 13, 1984
    Date of Patent: January 7, 1986
    Assignee: Dravo Corporation
    Inventors: Leonard L. Frauen, Stanley Kasper
  • Patent number: 4563273
    Abstract: There is disclosed a screening assembly for separating fines from a miscella stream including same and comprised of a screening element angularly disposed in a housing assembly beneath an inlet conduit means and over a miscella collection zone.
    Type: Grant
    Filed: March 27, 1981
    Date of Patent: January 7, 1986
    Assignee: Dravo Corporation
    Inventor: Donald A. Gessler
  • Patent number: 4548315
    Abstract: A tracked vehicle is tethered so that as it skids on a pile of bulk material, the cleated tracks transfer the material toward the tethered end. The tethering rope hitch point on the vehicle is translatable laterally to effect controlled sideward skiding for sweeping bulk material from a wide area and is located at one end above the vehicle center of gravity so that the vehicle can be lowered by the tethering rope through narrow openings in storage chambers yet come to rest upright. The tracks comprise cleated endless belts coupled to endless wire ropes at the end pulleys by resilient rail members made of two rows of discrete blocks bolted to the belts which are wedged against the wire ropes by grooves in the pulleys so that tension induced in the wire ropes resists the lateral forces tending to cause the belts to creep along the pulleys.
    Type: Grant
    Filed: June 7, 1983
    Date of Patent: October 22, 1985
    Assignee: Dravo Corporation
    Inventor: Aubrey C. Briggs
  • Patent number: 4512260
    Abstract: The piston rod of at least one hydraulic cylinder is axially connected to a pivot pin about which the car holding arm of a car holding device rotates in a vertical plane to engage the couplings between railroad cars. In the case of a single hydraulic cylinder, the inner chamber of the cylinder, located closest to the car holding arm, is connected to the outer chamber on the other side of the piston by a conduit. When hydraulic cylinders are connected to each pivot pin of the car holding arm, the inner chambers of the two cylinders are interconnected by a conduit as are the two outer chambers. When flow through the conduits is blocked by a solenoid valve, movement of the car holding arm in the direction parallel to the track is resisted and the arm holds the train in position.
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: April 23, 1985
    Assignee: Dravo Corporation
    Inventors: Edward T. Manning, Jr., Grant S. Horan
  • Patent number: 4506781
    Abstract: An endless belt with bottomless buckets or other gripping elements bolted to its outer surface at spaced locations, has endless wire ropes each loosely received in a longitudinal bore formed in confronting faces of two rows of discrete blocks of resilient material bolted to the inner surface of the belt to form a continuous rail member. The wire ropes are firmly coupled to the endless belt as they pass around end pulleys together by the wedging action created as the tension in the endless belt pulls the associated two rows of discrete blocks which have tapered side walls down into peripheral grooves in the end pulleys which also have tapered, but slightly narrower side walls. With the belt firmly coupled to the wire ropes, radial digging forces tending to pull the belt away from the end pulleys, and lateral forces generated as the digger is advanced into a pile of bulk material on a bias which tends to cause the belt to creep laterally on the pulleys, are resisted by tension developed in the wire ropes.
    Type: Grant
    Filed: June 7, 1983
    Date of Patent: March 26, 1985
    Assignee: Dravo Corporation
    Inventor: Aubrey C. Briggs
  • Patent number: 4501539
    Abstract: The drain openings in movable and fixed platens in a press unit are wider than the largest praticle in a slurry to be dewatered and are formed by arcuate ribs dimensioned to resist the transverse forces developed as the granular particles from bridges across the slotted drain openings in rendom order. Liquid expressed through the movable platen is directed radially outward through a subplaten, passes back through the clearance between the piston carrying the movable platen and the mold wall and is discharged through a sealing and collecting ring having a series of annular grooves which communicate with longitudinal radially extending slots having longitudinal bores at the radial extremity thereof which direct the liquid to an annular passage for discharge.
    Type: Grant
    Filed: December 2, 1983
    Date of Patent: February 26, 1985
    Assignee: Dravo Corporation
    Inventors: Edward A. Fenton, Jr., Ira W. Lakin, Joseph H. Stein, John R. Lohr, David A. Schreiber
  • Patent number: 4490237
    Abstract: As hot oil depleted shale from an indirect retorting process passes downward through a vertical shaft furnace, the residual carbon in the shale is burned out in the upper portion by air fed into the top of the furnace. The temperature of combustion is moderated by an inert gas also fed into the top of the furnace. Additional inert gas fed into the bottom of the furnace flows upward in countercurrent contact with the descending hot shale to cool the shale and heat the inert gas. The downwardly flowing gases from the upper, combustion portion of the furnace and the upwardly flowing gas from the lower, cooling portion are withdrawn from the furnace intermediate the upper and lower portions. The inert gas can be recycle gas which is heated by direct contact with the hot shale, a separate inert gas which is circulated through the heat exchanger to heat the recycle gas or a combination of the two.
    Type: Grant
    Filed: July 1, 1983
    Date of Patent: December 25, 1984
    Assignee: Dravo Corporation
    Inventors: Louis H. Jaquay, Albert C. Mengon, deceased