Underfeed Patents (Class 110/283)
  • Patent number: 10816268
    Abstract: A grate bar (for forming a plank of a conveyor grate for transporting bulk material) includes at least an up-facing surface for supporting bulk material, a down-facing surface for supporting the grate bar on at least one grate bar rest, front end and rear-end sides, first and second profiled narrow sides. The first and second profiled narrow sides are complementary to one another and form a moving gap therebetween if and/or when the first profiled narrow side of the chosen grate bar is positioned adjacent to the second profiled narrow side of a neighboring grate bar (that is identical to the chosen grate bar at least with respect to the profile of the second profiled narrow side). The grate bar can be easily replaced if a front edge between the up-facing surface and the front-end side has a front edge curvature, a rear edge between the up-facing surface and the rear-end side has a rear edge curvature and the rear edge curvature is complementary to the front edge curvature.
    Type: Grant
    Filed: September 25, 2019
    Date of Patent: October 27, 2020
    Assignee: Alite GmbH
    Inventor: Karl von Wedel
  • Patent number: 10760787
    Abstract: A grate block for a combustion grate, wherein consecutive grate blocks are arranged in a staircase and are designed to rearrange and convey the combustible material during combustion through pushing motions. The grate block includes a block body, an upper wall forming a supporting surface, and an extension parallel to a longitudinal axis L of the body. The supporting surface drops into a pushing surface formed by a front wall, which has at least one air supply opening for supplying air to the combustion grate, which extends at a right angle or slant to the pushing surface. In the lowest region of the front wall, formed as a foot, which lays on the supporting surface of a grate block, is adjacent in the pushing direction. The front resting edge of the pushing surface is arranged in a plane E extending at a right angle to the longitudinal axis L.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: September 1, 2020
    Assignee: HITACHI ZOSEN INOVA AG
    Inventors: Werner Brennwald, Helen Gablinger
  • Patent number: 10309649
    Abstract: [Problems to be Solved] An exhaust duct (4) for assembly into a combustion apparatus has: a burner (1) to eject air-fuel mixture downward; and a combustion box (3) disposed on a lower side of the burner (1). The exhaust duct includes: a riser duct section (42) elongated in a vertical direction and having, at a lower portion thereof, an inlet port (41) connected to an exhaust port (35) for combustion gas which is opened in a lower portion of the combustion box (3); and a flat horizontal duct section (43) bent at an upper end of the riser duct section (42) so as to be elongated forward. By restraining the resonance of an upper wall part (431) and a lower wall part (432) of the horizontal duct section (43), noises due to resonance sounds are reduced. [Solving Means] The natural frequencies in an upper wall part (431) and the lower wall part (432) of the horizontal duct section (43) are varied from each other.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: June 4, 2019
    Assignee: RINNAI CORPORATION
    Inventor: Takahiro Ono
  • Patent number: 8591608
    Abstract: A gasifier includes a combustion zone where a gas is introduced and fuel is combusted and at least one sensor for measuring a predetermined condition in the gasifier. A grate subsystem contains the fuel and includes at least one grinding mechanism. A controller is responsive to the at least one sensor and controls the grinding mechanism by activating the grinding mechanism if the predetermined condition exists to reduce the collection of non-fuel products on the grate subsystem.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: November 26, 2013
    Assignee: MSW Power Corporation
    Inventors: Matthew Young, Steven Anthony, Stephen Armstrong, Steven Chase
  • Patent number: 5906194
    Abstract: A side edge assembly for a cooling grate comprises a first aligned array of outer plates arranged in succession in the longitudinal direction of the grate and a second aligned array, which is between the grate and the outer plates, of inner plates arranged in succession in the longitudinal direction of the grate. In the assembled condition the joins of the outer plates and the joins of the inner plates are displaced relative to each other in the longitudinal direction.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: May 25, 1999
    Inventor: Karl Von Wedel
  • Patent number: 5497711
    Abstract: Improved grate plates are designed to produce multiple eddy currents in the absence of clinker and to provide even greater air distribution when overlaid by clinker. Each grate plate has a plurality of upwardly flaring wells which open to the upper surface on which the clinker bed is supported. Within each well is at least one semi-annular slot providing ingress for cooling air from a remote source. The slot extends only partially around the wall of the well such that air is injected into the well somewhat tangentially to the flaring surface to induce cyclonic motion of the air which is enhanced by the flared conic walls of the wells. Accordingly, the energy imparted the air by injection is diminished by the rotational energy dissipated and the cooling air's initial vertical component of velocity is diminished.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: March 12, 1996
    Assignee: Southern Alloy Corporation
    Inventor: Billy T. Bobbitt
  • Patent number: 5271339
    Abstract: A combustion apparatus for a refuse incinerator has a plurality of rows of grates arranged in parallel in the directions of breadth and in series in the longitudinal directions of a combustion zone and a post-combustion zone of the combustion apparatus. The rows consist of immobile grates and mobile grates alternately arranged. Immobile girders support the immobile grates. Mobile girders support the mobile grates. A partition wall divides the combustion apparatus into the combustion zone and the post-combustion zone. Seals cooperates with the mobile girders and are located on the partition wall. A hydraulic cylinder shuttles the mobile girders. Bearing housings are mounted on upper protrusions of the mobile girders holding the mobile grates so as to be able to vibrate.
    Type: Grant
    Filed: November 6, 1991
    Date of Patent: December 21, 1993
    Assignee: NKK Corporation
    Inventors: Miki Yamagishi, Sadao Suzuki, Shigeyuki Doi
  • Patent number: 5265587
    Abstract: An apparatus for preventing ash build-up and clinker formation of a particulate fuel mass in a stove includes a grate having a plurality of openings therein and on which the particulate fuel mass resides. A bottomless container retains the particulate fuel mass on the grate. The grate is reciprocated with respect to the bottomless container and the particulate fuel mass such that the position of the grate openings is altered relative to the particulate fuel mass to channel stove air flow through various portions of the particulate fuel mass.
    Type: Grant
    Filed: March 27, 1992
    Date of Patent: November 30, 1993
    Inventor: Timothy R. Carlson
  • Patent number: 5197397
    Abstract: A grate structure for a horizontal type incinerator has a plurality of rows of grates arranged in parallel in perpendicular X and Y directions of the incinerator. Each X-direction row has a series of immovable grates and a series of movable grates alternating with the immovable grates. The immovable grates and movable grates are supported at a predetermined angle of .theta..sub.1 relative to a surface of the immovable supporting member. The immovable grates are pivotally mounted on an immovable support and the movable grates are pivotally mounted on a sawtooth shaped movable support. The free forward end of each grate rests on the adjacent grate. The movable grates are reciprocated back and forth along the upper surfaces of the immovable grates. In the Y direction, each row of grates is pivoted on a common axle by way of a common bearing member.
    Type: Grant
    Filed: April 11, 1991
    Date of Patent: March 30, 1993
    Assignee: NKK Corporation
    Inventors: Miki Yamagishi, Sadao Suzuki, Shigeyuki Doi
  • Patent number: 4966548
    Abstract: The heat treatment of solids by combustion, cooling, or the like with the aid of gas may take place on a grate conveying such solids while the gas is passed through openings in the surface of the grate. In order to provide lateral clearances of such grates with the same order of narrowness as the majority of the grate's openings, the mobile framework of the grate is suspended by tension elements inclined at an angle of at least 3 degrees relative to the perpendicular. If the mobile frame deviates from a straight course, the inclined suspension creates a centering force guiding the mobile frame without mechanical contact and wear. As a result, the lateral clearances for thermal expansion and building tolerances are reduced from about 20 to 2 mm.
    Type: Grant
    Filed: December 22, 1989
    Date of Patent: October 30, 1990
    Inventor: Karl von Wedel
  • Patent number: 4922889
    Abstract: A heater for burning combustible pelletized fuel. The pelletized fuel is delivered at a controllable rate to a double-walled burn pot in an enclosed combustion chamber. Combustion air is injected into the combustion chamber at a pressure higher than the ambient air pressure surrounding the heater. Combustion air is injected between the walls of the burn pot through ports in the inner wall into the fuel at or slightly below the top of the fuel level. Additional combustion air is injected approximately horizontally across the top of the burn pot through an injection air manifold. Crossfire injection air is injected approximately vertically about the periphery of the burn pot, confining fumes and exhaust air directly above the burn pot. Heated exhaust gasses rise to the top of the combustion chamber and are drawn from the combustion chamber through a heat exchange unit surrounding the combustion chamber. The exhaust gasses are drawn from the combustion chamber by suction created by and extraction air mechanism.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: May 8, 1990
    Assignee: Thermic, Inc.
    Inventors: David Nuesmeyer, Gary Brondt
  • Patent number: 4762489
    Abstract: The cooling apparatus which is preferably constructed in the form of a grate cooler contains in its material inlet portion a material transfer arrangement with at least two rows lying behind one another of transversely extending air boxes which can be supplied with air and have upper surfaces with air holes. The clear opening width of these air holes (area for the air to pass through) is adjustable, so that all air boxes can be supplied independently of one another with adjustable quantities of air. In this way the streams of cooling air can be adapted to differing local ranges of grain sizes of the clinker on the material transfer arrangement.
    Type: Grant
    Filed: April 10, 1987
    Date of Patent: August 9, 1988
    Assignee: Krupp Polysius AG
    Inventors: Heinz-Herbert Schmits, Hermann Niemerg
  • Patent number: 4520740
    Abstract: Combustion and heating equipment includes a body with an underfeed stoker located in the lower part thereof. A jacket surrounds the body to define a heating space, different parts of which are interconnected by triangular ducts disposed in the gas pass. A screwfeeder is provided for the retort of the stoker and extends right through the body terminating in an inlet 36. A mobile hopper has an outlet for registry with the inlet and is refillable and interchangeable.
    Type: Grant
    Filed: March 21, 1983
    Date of Patent: June 4, 1985
    Assignee: Coal Industry (Patents) Limited
    Inventor: Brian M. Carpenter
  • Patent number: 4512266
    Abstract: A city refuse incinerator provided with stoker type firing equipment for combustion of city refuse has gas injectors installed low on the inside of a furnace body to inject low temperature inert combustion exhaust gas, purified in a dust collector, so that a gas curtain is formed on the inner surface of side walls of the furnace by the low temperature inert gas, thus preventing the formation of clinkers.
    Type: Grant
    Filed: March 27, 1984
    Date of Patent: April 23, 1985
    Assignee: Kabushiki Kaisha Takuma
    Inventor: Masanobu Shigaki
  • Patent number: 4510873
    Abstract: Stoker type firing equipment for use with a city refuse incinerator provided with step type stokers formed by combining movable fire grates and fixed fire grates alternately and gas injectors installed in the fixed fire grates inject low temperature inert gas onto burning refuse, thus allowing free control of burning rate and burning temperature of the refuse by injecting the low temperature inert gas through the gas injectors.
    Type: Grant
    Filed: March 19, 1984
    Date of Patent: April 16, 1985
    Assignee: Kabushiki Kaisha Takuma
    Inventor: Masanobu Shigaki
  • Patent number: 4389978
    Abstract: A grate characterized in that a fuel supporting and conveying surface is provided comprising at least one elongate channel having an open mouth and a bottom, the or each of said channels having a transverse cross-section which decreases in width in a direction extending away from the open mouth towards the bottom of the channel, air feed opening means to feed air to the interior of the channel at least in the region of the bottom thereof, and means mounting the channel to permit the channel to be vibrated to cause fuel to be conveyed along the channel and longitudinally of the grate.
    Type: Grant
    Filed: June 9, 1981
    Date of Patent: June 28, 1983
    Assignee: Parkinson Cowan GWB Limited
    Inventor: Reginald D. Northcote
  • Patent number: 4300460
    Abstract: A combustion method in which heat is generated from particulate laden combustible gas containing mineral matter created from gasifying waste wood, coke or other combustible material in which the waste is fed into a pile, under-fire combustion air dries and gasifies the waste, oxidizing the fixed carbon in a first chamber to generate heat at a temperature less than the melting temperature of the non-combustible material so as not to form slag, adding air in the first chamber in an amount less than stoichiometric with the air introduced in a swirling fashion to move the particulate laterally away from the discharge of the primary chamber, impeding the movement of this particulate also by adding secondary combustion air in a downward swirling direction in the secondary chamber so that very little non-combustible material reaches the second chamber where melting can occur.
    Type: Grant
    Filed: May 18, 1979
    Date of Patent: November 17, 1981
    Assignee: Enterprises International Inc.
    Inventors: Frank H. Lamb, Malcolm D. Lefcort, Petr Rada
  • Patent number: 4177740
    Abstract: A combustion apparatus having primary and secondary combustion chambers burns waste wood with an optional third chamber. The third chamber is used to blend the combustion products down to the desired process temperature. High pressure swirl air is admitted tangentially to the primary chamber above a burning fuel pile. The swirl air reacts with a small proportion of the pyrolized gases to maintain a steady temperature at the exit from the primary chamber. The swirl air also centrifugally separates particulate matter from the gas stream leaving the primary chamber. The total quantity of underfire and swirl air is closely controlled to maintain substoichiometric conditions in the primary chamber. Secondary air complete combustion of the pyrolized volatiles in the secondary chamber. The secondary air is admitted tangentially to establish a rotating mass of relatively cool combustion air adjacent to the walls of the secondary combustion chamber.
    Type: Grant
    Filed: March 10, 1978
    Date of Patent: December 11, 1979
    Assignee: Enterprises International, Inc.
    Inventors: Frank H. Lamb, Malcolm D. Lefcort, Petr Rada