Fluorspar Application

Fluorspar application in the hydrofluoric acid (HF) industry

The reaction of fluorspar by CaF2 formula with sulfuric acid and heating in a furnace produces hydrogen fluoride (HF) gas and calcium sulfate. After purification by scrubbing, condensation, and distillation, the HF is sold as anhydrous HF, a colorless fuming liquid; or it may be absorbed to form aqueous acid, usually 70% HF. Synthetic cryolite, organic or inorganic fluoride chemicals, and elemental fluorine are made from hydrofluoric acid.

The acid itself is important in the catalyst for the production of alkylates, a substance found in high-octane fuels for aircraft and piston-powered vehicles, in pickling steel, in the removal of enamel, and in the etching and polishing of glass, and in various electroplating operations.

Fluorspar application in the Metallurgical Industry

Fluorspar Application as a flux with lime to improve the fluidity of slag in steelmaking and ladle metallurgy. Fluorine promotes the fluidity of slag (by lowering its melting point) and thus enables the removal of sulfur and phosphorus from the steel into the slag. Fluorspar application in steelmaking at 2 to 10 kg or 5 to 10% of the added lime. Fluorite is used in the treatment of electrolytic slag at a ratio of 70 to 30 fluorspar to lime.

The objective in electrolytic slag treatment is to form a highly conductive slag with the required melting temperature. In aluminum smelting, about 23 kg of AlF3 equivalent is used per ton of aluminum. Fluorspar serves similar purposes in iron foundries, where it is added to the charge of the blast furnace at a rate of about 7-9 kg/ton of molten metal.

Fluorite (fluorine or fluorospar) in the cement industry

Fluorspar application as a flux in cement production. CaF2 added to the cement raw material mix before it enters the rotary kiln; the addition of this mineral allows the kiln to operate at a lower temperature, making it more economical. Fluorite also helps produce a softer clinker product that is easier to grind, resulting in increased electrical energy.

Fluorite or fluorspar application in the glass industry

Fluorspar application in the glass industry to make flint glass, white or milky colored glasses, and glazes. Flint glass mixtures usually contain 3% fluorspar. Milk glasses contain 10-20% fluorine and are used in antique glassware, sanitary ware, and restaurants. Opaque glazes are used to coat stoves, refrigerators, cabinets, bathtubs, and cookware, and for facing bricks, tiles, and other building materials.

Fluorine Welding Electrode Coating

Basic electrodes have calcium fluoride (fluorspar-fluorine) in their coating. The decomposition of calcium carbonate forms carbon dioxide and carbon monoxide, which protects the arc from contamination and as a result, a small amount of sulfur and oxygen remains in the weld metal.

Therefore, the strength and toughness of this weld are among the strongest welds produced by this type of electrode and its resistance to cracking is also higher. Basic electrodes produce a slag with a lower melting point than rutile and acid electrodes, which means that even if the slag is not completely separated between passes, the risk of slag entering is small.

Other uses of fluorite (fluorspar)

Fluorspar of ceramic grade is used in the production of magnesium and calcium metals and in the preparation of some manganese chemicals. In current industrial operations, consumers prefer to purchase acid grade fluorite rather than ceramic grade and dilute it accordingly. Ceramic and metallurgical grade fluorite may be used in the manufacture of fiberglass insulation, in zinc smelting, as a green vanadium foam inhibitor in the production of pea-colored facing bricks, and as an abrasive on some types of sandpaper.

Various grades of fluorite are used in the production of calcium carbide in electric furnaces, in the manufacture of electrodes, for arc lamps, and as a bonding agent for grinding wheels. Various types of welding rod coatings are composed of fluorite or fluorite mixtures. Fluorite is used in the production of magnesium and calcium metals and in the preparation of some manganese chemicals.