Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23K—FEEDING FUEL TO COMBUSTION APPARATUS
  • F23K3/00—Feeding or distributing of lump or pulverulent fuel to combustion apparatus
  • F23K3/22—Controlling thickness of fuel bed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23K—FEEDING FUEL TO COMBUSTION APPARATUS
  • F23K3/00—Feeding or distributing of lump or pulverulent fuel to combustion apparatus
  • F23K3/10—Under-feed arrangements
  • F23K3/14—Under-feed arrangements feeding by screw
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F27—FURNACES; KILNS; OVENS; RETORTS
  • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
  • F27D21/00—Arrangements of monitoring devices; Arrangements of safety devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F27—FURNACES; KILNS; OVENS; RETORTS
  • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
  • F27D3/00—Charging; Discharging; Manipulation of charge
  • F27D3/08—Screw feeders; Screw dischargers

Definitions

• the present invention relates to a feeder apparatus.
• the present invention relates to a feeder apparatus for a metallurgical furnace that reduces the emission of fugitive gases from the furnace.
• feed material is supplied to the furnace through a feed port in the furnace roof.
• feed material is supplied to the furnace on a conveyor which deposits the feed material through an open port.
• fugitive gases such as sulphur dioxide
• fugitive gases escaping from the furnace may carry fine particles of the material being treated, representing a loss of metal recovery.
• fugitive gases may refer to either gaseous emissions from the furnace, or a combination of gaseous emissions and entrained particulates. It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country. Throughout this specification, the term “comprising” and its grammatical equivalents shall be taken to have an inclusive meaning unless the context of use indicates otherwise. Summary of the Invention.
• a feeder apparatus for a furnace comprising a vessel for feed material, said vessel being positioned at least partially above a feed port of the furnace, and feeding means located at least partially within the vessel, said feeding means being adapted to control the rate of feed flow from the vessel, through the feed port and into the furnace, said apparatus preventing escape of fugitive gases between an exterior of the vessel and the feed port.
• the vessel may be of any suitable size, shape or configuration.
• the vessel comprises one or more walls defining an internal region in which the feed material is retained.
• the vessel may be of any suitable shape.
• the vessel may be substantially square or rectangular in cross-section.
• the vessel may be substantially circular or oval in cross-section.
• the vessel comprises a hopper, holding tank or the like adapted to retain a quantity of feed material therein.
• the exact configuration of the vessel is not critical, although a skilled addressee will understand that it would be beneficial if the vessel was substantially conical in shape across at least a portion of its height so as to facilitate the flow of feed material through the vessel and to minimise the amount of feed material adhering or being caught on the internal walls of the vessel.
• the conical portion of the vessel tapers inwardly from an upper portion of the vessel to a lower portion of the vessel at or adjacent the feed port of the furnace.
• the vessel may be substantially conical across its entire cross-section.
• the vessel may comprise an upper conical portion and a lower throat portion, the throat portion being positioned adjacent the feed port of the furnace.
• the throat portion may be of any suitable shape, although in some embodiments the throat portion may be substantially cylindrical.
• the vessel is positioned at least partially above the feed port of the furnace.
• the lower section of the vessel is at least partially positioned within the feed port of the furnace so as to prevent the fugitive gases escaping to atmosphere by flowing out past an exterior surface of the vessel.
• the vessel may be positioned such that a portion of the lower section of the vessel is at least surrounded by the feed port. More preferably, the feed port entirely surrounds the lower portion of the vessel, with the perimeter matching the feed port perimeter.
• the feed port entirely surrounds the lower portion of the vessel and a seal is achieved between the feed port and the vessel.
• the lower section of the vessel is adapted to abut the edge of the feed port. More preferably, the lower section of the vessel is adapted to form a seal with the edge of the feed port.
• the lower section of the vessel itself may form a seal, or sealing means (such as gaskets, O-rings or the like) may be provided to create a seal between the vessel and the feed port.
• a chemical sealant such as resin, adhesive, silicone or the like, or a combination thereof
• the feed port and the lower section of the vessel may be fixed to one another (such as by welding or bolting) to create a seal.
• high tolerance shrouds, adjustable collars or the like may be used.
• the vessel is positioned above and entirely surrounds the feed port.
• the vessel may form a seal with the furnace such that fugitive gases cannot escape between the vessel and the furnace.
• the feeding means may be of any suitable form, such as a screw feeder, valve, door (or pair of doors), vibratory feeder, pozzalanic feeders or the like that, when actuated, cause a flow of feed material to pass from the vessel into the furnace.
• the feeding means is adapted to control the rate of flow of feed material between the vessel and the furnace.
• the control of the rate of flow of feed material may be achieved in any suitable manner, however in a preferred embodiment, the rate of flow of feed material is controlled by using a variable speed feeding means.
• the feeding means comprises a screw feeder (and particularly a vertical screw feeder) associated with drive means in the form of a variable speed motor or the like.
• a screw feeder comprises a central shaft or post and one or more helical screw flights extending outwardly from the shaft.
• the length of the screw need only be relatively short to control the head of feed material positioned above the screw and to prevent the feed material from being delivered in an unreliable manner.
• the screw may be a helical screw.
• the feeding means may be positioned at any suitable location.
• the feeding means may be positioned substantially within the throat portion of the vessel.
• the feeding means may be located within the conical portion of the vessel.
• the feeding means may be located in both the conical portion and the throat of the vessel.
• the apparatus may be provided with cleaning means.
• the shaft of the screw feeder may be provided with cleaning means to ensure that the feed port in the furnace is maintained free of any buildup of material to prevent blockages and ensure a reliable supply of feed material to the furnace.
• any suitable cleaning means may be provided, such as, but not limited to, one or more scraper bars, brushes, wedges, blades or the like, or a combination thereof.
• the one or more helical screw flights may be provided with reaming flights adapted to maintain the feed port clear of any buildup of material.
• the invention may incorporate vibration means and controlled blasting methods such as air blasting to prevent any buildup of material.
• the feeding means is adapted to be positioned adjacent, or even abut, an inner wall of the vessel along substantially the entire height of the feeding means.
• the feeding means when the feeding means is located at least partially in the conical portion of the vessel, the feeding means may also be substantially conical in shape such that the outer periphery of the feeding means lies substantially parallel to the inner wall of the vessel.
• the outer periphery of the feeding means may abut the inner wall of the vessel such that feed material is unable to flow past the feeding means when the feeding means is not operational.
• the outer periphery of the feeding means may be spaced apart from the inner wall of the vessel.
• the feed material may be incapable of flowing past the feeding means when the feeding means is not operational due to, for instance, the angle of repose of the particles in the feed material in the vessel, and the angle of the walls of the vessel.
• material is only fed to the furnace when the feeding means is operated.
• the position of the feeding means within the vessel may be adjusted as desired.
• the feeding means may be raised or lowered as required within the vessel (or even lowered at least partially through the feed port and into the furnace).
• the feeding means may be adapted to be removed completely from the vessel, such as when maintenance or repair to the feed port, vessel or feeding means is required.
• the feeding means and the vessel may be removed together from the roof of the furnace. In this embodiment the contents of the vessel would remain undisturbed while the feeding means and vessel were removed as one combined unit.
• the removal of the feeding means and the vessel may be integrated with the structure and motion of the upstream equipment: i.e. the feed transfer means.
• the feeding means is associated with one or more moveable support members.
• the moveable support members may be of any suitable form, such as a boom member capable of being raised or lowered, a retractable or telescoping member, a folding member or the like, or a combination thereof.
• the one or more moveable support members are adapted for attachment to a support frame that may be raised and lowered as desired, or even retracted when the feeding apparatus is removed for maintenance.
• the support frame may comprise one or more frame members (for instance, one or more vertical members and/or one or more horizontal members), including one or more retractable or telescoping members as required. A skilled addressee will understand that the exact construction of the support frame is not critical.
• the feeding means may be lowered using other techniques, such as a pulley arrangement, hydraulics, forklift, crane or the like.
• the feeding means may be raised or lowered using automated or manual techniques.
• the feeder apparatus may further comprise feed transfer means adapted to transfer feed material into the vessel.
• feed transfer means may be provided, such as, but not limited to, one or more elevators, chutes, conveyors, pipes or the like.
• feed material may be transferred to the vessel directly from a truck, loader, or similar vehicle, or may be manually transferred to the vessel, such as by a worker using a spade or shovel.
• the vessel may be provided with no upper wall, or may be provided with only a partial upper wall.
• an upper wall may be provided on the vessel and the feed transfer means may be adapted to transfer feed material into the vessel through an opening or port in the upper wall.
• the rate at which feed material is transferred into the vessel is substantially the same as the rate at which feed material is fed from the vessel into the furnace.
• the volume of feed material in the vessel is maintained at a substantially constant level.
• This substantially constant level of material may be achieved using any suitable technique.
• the feeding apparatus may be provided with one or more sensing means to determine the level of feed material within the vessel. Any suitable sensing means may be provided, including one or more load sensors, contact sensors, level sensors, one or more cameras for monitoring the level and so on. Alternatively, the level may be monitored manually.
• the one or more sensing means may relay signals regarding the level of the feed material in the vessel (or the rate of change of the level of the feed material in the vessel) to any suitable receiving means, such as a DCS, PLC, computer or other means using non stationary receiving means such as PDA, mobile telephones and so on.
• any suitable receiving means such as a DCS, PLC, computer or other means using non stationary receiving means such as PDA, mobile telephones and so on.
• the receiving means may then take the appropriate action to ensure that the level of feed material is maintained at a substantially constant level. For instance, if the level of feed material in the vessel begins to drop below a desired level, a signal may be sent (automatically by an expert control system, DCS or the like) to increase the rate at which the feed transfer means transfers feed material into the vessel.
• a signal may be sent to decrease the rate at which the feed transfer means transfers feed material into the vessel.
• This system may be operated with aural signals and/or visual signals such as sirens, flashing lights or the like to alert workers in the area if required.
• an aural signal a siren or the like
• a visual signal such as a flashing light
• control strategy implemented with the present invention should ensure safe and reliable operation of the furnace to obtain the highest possible safety standards and consistent yield and quality from the furnace.
• the level of feed material maintained in the vessel may be any suitable level. However, it is preferred that the level of feed material is maintained at such a level that the feed material forms a substantially gas impermeable plug or barrier in order to reduce (or eliminate) fugitive gases escaping from the furnace.
• the exact volume of feed material required to form a substantially gas impermeable plug or barrier will depend on a number of properties of the feed material, including density, porosity, moisture content and the like. Thus, the volume of feed material required to form a substantially gas impermeable plug or barrier will vary depending on the feed material being used.
• forming a gas impermeable plug or barrier of feed material also reduces (or eliminates) the flow of unwanted gases into the furnace.
• the flow of gases into a furnace generally results in localized cooling within the furnace, which, in turn, reduces the efficiency of operation of the furnace.
• the feeder apparatus may be used in a wide variety of furnaces known to a person skilled in the art.
• the feeder apparatus may be used in any suitable furnace, such as, but not limited to, bath-type furnaces (including vertical furnaces), electric furnaces, top submerged lance furnaces, blast furnaces, furnaces with top feed ports or the like.
• the feeder apparatus is used with a top submerged lance furnace, although it will be appreciated that the invention is not limited to use only with this type of furnace.
• the invention resides broadly in a feeder apparatus for a metallurgical furnace comprising a vessel for feed material, said vessel being positioned at least partially above a feed port of the furnace so as to prevent the escape of fugitive gases between an exterior of the vessel and he feed port, a vertical screw feeder positioned at least partially within the vessel, and drive means for driving the vertical screw feeder, wherein the flow of feed material from the vessel into the furnace is controlled to ensure that a sufficient quantity of feed material is retained in the vessel to reduce the egress of fugitive gases from the furnace through the feed port.
• an apparatus for reducing emissions from a metallurgical furnace comprising a vessel for feed material, said vessel being positioned at least partially above a feed port of the furnace so as to prevent the escape of fugitive gases between an exterior of the vessel and he feed port, feed transfer means for transferring feed material into the vessel and feeding means located at least partially within the vessel and adapted to control the rate of feed flow from the vessel into the furnace, wherein the rate of flow of feed material from the vessel into the furnace is substantially the same as the rate of flow of feed material from the feed transfer means into the vessel so as to ensure that a sufficient quantity of feed material is retained in the vessel to reduce the egress of fugitive gases from the furnace through the feed port.
• Figure 1 illustrates a schematic view of a feeder apparatus according to an embodiment of the present invention
• Figure 2 illustrates a schematic view of a portion of a feeder apparatus according to an embodiment of the present invention.
• FIG. 3 illustrates a schematic view of a portion of a feeder apparatus according to an embodiment of the present invention. Detailed Description of the Drawings.
• FIG. 1 there is illustrated a feeder apparatus 10 according to an embodiment of the present invention.
• the feeder apparatus 10 comprises a vessel 11 positioned at least partially above a feed port 12 of a metallurgical furnace 13.
• the lower section of the vessel 11 is positioned within the feed port 12 such that a seal is formed at the point at which the feed port 12 and vessel 1 1 abut. The formation of this seal prevents fugitive gases from escaping from the furnace 13 through gaps between the feed port 12 and the vessel 1 1.
• the apparatus 10 comprises feeding means in the form of a screw feeder 14.
• the screw feeder 14 comprises a drive shaft 15 and a screw flight 16 positioned within the vessel 11.
• the vessel 1 1 is supplied with feed material 17 (such a mineral concentrate) which may then be feed into the furnace 13 on actuation of the feeder apparatus 10.
• feed material 17 such a mineral concentrate
• FIG 1 it may be seen that the angle and positioning of the screw flight 16 substantially prevents the feed material 17 from entering the furnace 13 while the screw feeder 14 is not operational. This effect may also be aided by the nature of the feed material 17, its moisture content, angle of repose and so on. While in this position, the feed material 17 effectively forms a solid plug of material that prevents emissions (gases, particulates etc) from escaping to the atmosphere through the feed port 12 of the furnace 13.
• One end of the drive shaft 15 is connected to drive means, such as a motor 18 which, when actuated, rotates the drive shaft 15 in the direction indicated by arrow 19. Actuation of the drive shaft 15 cause rotation of the screw flight 16 which, in turn, causes feed material 17 to be fed into the furnace 13 through the feed port 12.
• drive means such as a motor 18 which, when actuated, rotates the drive shaft 15 in the direction indicated by arrow 19.
• Actuation of the drive shaft 15 cause rotation of the screw flight 16 which, in turn, causes feed material 17 to be fed into the furnace 13 through the feed port 12.
• Feed material 17 may be provided to the vessel 11 using any suitable technique such as a conveyor or elevator, or by feeding material into the vessel 1 1 from a truck, loader, filter or the like.
• the feeder apparatus 10 may be provided with a support frame including a horizontal member 19 and a vertical member 20.
• the vertical member is provided as a telescopic or retractable member that is associated with a base member 21.
• the base member 21 is bolted or otherwise attached to the floor or ground, or other suitable support.
• Providing the vertical member 20 as a telescopic member enables the vertical member 20 to be raised when removing the screw feeder 14 from the vessel 11 and lowered when positioning the screw feeder 14 within the vessel 1 1.
• the horizontal member 19 may then be used to displace the screw feeder 14 from the vessel 11 in a horizontal direction.
• the horizontal member 19 may also be a telescoping or retractable member that enables the screw feeder 14 to be moved away from the vessel 11 in a horizontal direction.
• the vertical member 20 may be adapted to pivot about its longitudinal axis so that the screw feeder may be pivoted away from the vessel 11.
• FIG 2 a schematic view of a portion of a feeder apparatus 10 according to an embodiment of the invention is shown.
• the vessel 11 is positioned entirely above the feed port 12 of the furnace 13.
• the vessel 11 is provided with a pair of flanges 22 that allow the vessel 11 to be connected to the roof of the furnace 13, for instance by bolting or welding.
• the connection of the flanges 22 to the furnace 13 forms a seal that prevents the escape of fugitive gases from the furnace 13 through gaps between the feed port 12 and the vessel 11.
• FIG 3 a schematic view of a portion of a feeder apparatus 10 according to an embodiment of the invention is shown.
• the vessel 11 is positioned entirely above the feed port 12 of the furnace 13 and entirely surrounds the feed port 12.
• the vessel 1 1 may either abut the roof of the furnace 13 or may be retained in position using any suitable fastening technique.
• the positioning of the vessel 1 1 forms a seal that prevents the escape of fugitive gases from the furnace 13 through gaps between the feed port 12 and the vessel 1 1.
• the feeder apparatus 10 provides the ability to reduce or even eliminate the escape of fugitive gases from a furnace through the feed port. This represents a significant advantage, environmentally and from a health and safety point of view.
• the ability to prevent the emission of fugitive gases from a furnace with minimal additional infrastructure represents an efficient and cost effective way to reduce emissions for new furnaces as well as retrofitting of existing furnaces. In addition it prevents the ingress of cooler gases into the furnace that produces cold spots within the furnace.
• the feeder apparatus of the present invention achieves these advantages while ensuring a constant and reliable feed of material to the furnace. Thus, minimal or no impact on operational effectiveness is envisaged when the present invention is in use.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Furnace Charging Or Discharging (AREA)
• Vertical, Hearth, Or Arc Furnaces (AREA)
• Manufacture And Refinement Of Metals (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (1)

Family

ID=45496380

Family Applications (1)

Country Status (10)

Families Citing this family (3)

Citations (3)

Family Cites Families (12)

• 2011
  • 2011-07-20 MX MX2012014035A patent/MX2012014035A/es not_active Application Discontinuation
  • 2011-07-20 RU RU2012148563/02A patent/RU2012148563A/ru not_active Application Discontinuation
  • 2011-07-20 CN CN201180034727.6A patent/CN103052860B/zh not_active Expired - Fee Related
  • 2011-07-20 PE PE2013000103A patent/PE20131121A1/es not_active Application Discontinuation
  • 2011-07-20 BR BR112013001402A patent/BR112013001402A2/pt not_active IP Right Cessation
  • 2011-07-20 AU AU2011282479A patent/AU2011282479B2/en not_active Ceased
  • 2011-07-20 CA CA2804294A patent/CA2804294A1/en not_active Abandoned
  • 2011-07-20 US US13/811,056 patent/US20130263764A1/en not_active Abandoned
  • 2011-07-20 WO PCT/AU2011/000927 patent/WO2012009763A1/en active Application Filing
  • 2011-07-20 JP JP2013519919A patent/JP2013534613A/ja active Pending

Patent Citations (3)

Also Published As

Similar Documents

Legal Events