Classifications

• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
  • C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
  • C03B5/26—Outlets, e.g. drains, siphons; Overflows, e.g. for supplying the float tank, tweels
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
  • C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
  • C03B5/26—Outlets, e.g. drains, siphons; Overflows, e.g. for supplying the float tank, tweels
  • C03B5/262—Drains, i.e. means to dump glass melt or remove unwanted materials

Definitions

• This invention concerns a melting furnace for the melting of mineral fibre raw material, the furnace comprising a bottom part, side walls and a cover, supply means for the raw material, as well as a discharge opening in the side wall for mineral melt arranged at a distance from the bottom part of the melting furnace, and a discharge opening for emptying the melting furnace, at the level of the bottom part.
• Mineral wool products of glass wool, rock wool and slag wool type are the most well known and used products for both heat and acoustical insulation.
• the iron oxide, or part thereof, contained in the mineral raw material or the slag is reduced to metallic iron and sinks to the bottom of the furnace in the form of an iron melt, which continuously increases in volume.
• the iron melt has to be removed at regular intervals from the melting furnace.
• the iron melt is removed through a discharge opening in the bottom of the melting furnace, whereby the iron melt is completely removed at each emptying operation. This method cf proceeding is used e.g. in the melting furnace according the Fl-patent application no 853458.
• the mineral melt formed during the melting process has a very corrosive effect on the walls of the melting furnace. This results in the fact that the melting furnace on its inside has to be provided with an extremely corrosion resistant lining, which is both expensive and difficult to apply.
• the iron melt which collects at the bottom of the melting furnace has a much gentler effect on the lining than the mineral melt. If it is possible to prevent the iron melt from sinking below a predetermined level, it is possible to use in the bottom part of the melting furnace a much cheaper lining.
• pig iron is added to the melting furnace prior to starting the introduction of rock raw material.
• the melting furnace comprises a bottom part 1, side walls 2 and a cover 3.
• a number of electrode rods 5, preferably of graphite, extend through the cover by means of which the raw material 9 is melted.
• This raw material 9 is introduced into the melting furnace by means of supply means (not shown), which are arranged to distribute the rock raw material 9 in a substantially even layer over the mineral melt 8 formed during the melting process.
• Mineral melt 8 is withdrawn during the melting process in a constant flow from the melting furnace through a discharge opening 4 arranged in the side wall 2 to a spinning device (not shown) for the formation of mineral fibres.
• the discharge opening 4 is situated at a level at a distance from the bottom part 2 of the melting furnace.
• the melting furnace is provided with a discharge opening 6 at the level of the bottom part 2.
• the two lower discharge openings 6 and 7 are suitably arranged in a common block, which according to a preferred embodiment is a carbon block divided into four parts, where the two outer parts, in which the respective discharge openings 6 and 7 are arranged, are replacable.
• the inside of the block is preferably covered with a lining mix 10.
• the discharge openings 6 and 7 are normally closed and are opened only when necessary. In order to prevent the level of the iron melt from reaching the opening 4 for the mineral melt, excess iron melt has to be removed at regular intervals. Normally excess iron melt 11 is removed from the melting furnace at about 2 to 3 months intervals.
• the discharge opening 7 is then opened using a drilling machine or by burning with oxygen. When the desired quantity of iron melt 11 has been withdrawn from the furnace, the discharge opening 7 is closed using a mud gun (not shown) which has been precharged with heated sealing mud. The drawing shows the state when all excess iron melt has been removed.
• the discharge opening 6 is opened only when the whole melting furnace is to be emptied, e.g. for service or for renewing the lining. Opening of the discharge opening 6 takes most conveniently place by burning with oxygen.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Furnace Housings, Linings, Walls, And Ceilings (AREA)
• Inorganic Fibers (AREA)
• Furnace Charging Or Discharging (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8530374

Family Applications (1)

Country Status (5)

Cited By (1)

Citations (2)

• 1990
  • 1990-05-04 FI FI902235A patent/FI85262C/fi not_active IP Right Cessation
• 1991
  • 1991-05-02 AU AU77429/91A patent/AU7742991A/en not_active Abandoned
  • 1991-05-02 EP EP19910908389 patent/EP0527169A1/en not_active Withdrawn
  • 1991-05-02 WO PCT/FI1991/000127 patent/WO1991017125A1/en not_active Application Discontinuation
  • 1991-05-02 CA CA002082147A patent/CA2082147A1/en not_active Abandoned

Patent Citations (2)

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