Another example of the use of vermiculite as a raw material or developing active ingredient in various production areas is its use as an insulation material in high temperature and industrial areas. Vermiculite-based products range from factory-made boards and panels to premixed coatings that can be applied to mechanical spraying and hand plaster. Such coatings can be used in the petrochemical industry and tunnel construction. It is produced from vermiculite ground before or after the expansion process according to the desired grain size December. The milled material is used for anti-noise coatings, condensed control paints, for the construction of covering materials and seals requiring high performance in marine, for the purpose of increasing the fire resistance of organic foams and other polymer-based systems. In addition, expanded vermiculite is used for coloring final products. Vermiculite is usually produced together with aluminum cement, fire clays and silicates for refractory and high temperature insulation, depending on the type and type of application
A wide range of products are produced that can withstand temperatures of more than 1100 ºC. Refractory products used in vermiculite:
• Fire bricks produced with calcined clay
• High alumina concretes
• High alumina condensed bricks, slabs and special shapes
• Products with silicate content
Due to the excellent thermal insulation and low density of vermiculite, it is used as a filling material in the production of steel and metal coatings in order to minimize temperature losses on molten steel in ingots and ladles. Pressed vermiculite blocks are used in high-temperature January and furnaces, incinerators, boiling, wood burning stoves and night storage heaters. Today, fiber insulation is also widely accepted. The products are made of simple blocks, electrical elements, screws, etc., which are designed in highly detailed molds. it is also used in fields.
Boards, Panels and Premixed Coatings
Vermiculitebased products range from factory made boards and panels to premixed coatings suitable for application by mechanical spray or by hand plastering techniques on a range of structures. These coatings have been used in the petrochemical industry and tunnel construction.
Special Coatings
Special coatings are produced with vermiculite milled before or after exfoliation according to the range of particle sizes required. Such milled or ground material may be used for the production of anti-drumming coatings; condensation control paints; high performance gaskets and seals and for upgrading the fire resistance of organic foams and other polymer based systems. Exfoliated vermiculite can be coloured to suit its end use (e.g. retail display).
Refractory and High Temperature Insulation
Vermiculite for refractory and high temperature insulation is normally bonded with alumina cements, fire clays and silicates to produce a wide range of vermiculite products which, depending on type and application can withstand hot face temperatures of up to 1,100ºC. The type of refractory products made using vermiculite are:
- pre-fired clay bonded insulation firebricks;
- castable high alumina concretes for back up insulation;
- high alumina bonded bricks, slabs and special shapes;
- silicate bonded insulating shapes and moulded products.
Steelworks and Foundries
Thanks to its refractory properties, good thermal insulation and low density, Vermiculite is used in steelworks and foundries, for hot topping molten steel to reduce heat loss from ingots and ladles and generally as a loose-fill insulator.
Silicate Bonded Shapes and Blocks
Pressed vermiculite block insulation can be used in high temperature kilns, furnaces, combustion plants, boilers, wood burning stoves and night storage heaters. It is becoming more widely accepted as an alternative for asbestos or man-made mineral fibre insulation. The units can vary from simple blocks to very intricate shapes designed to accommodate electrical elements, fixing screws etc.
