Mineral wool, mineral fibres or man-made mineral fibres are fibres Fiber, also spelled fibre, is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread. They are very important in the biology of both plants and animals, for holding tissues together. Human uses for fibers are diverse. They can be spun into filaments, string or rope, used as a component made from natural or synthetic minerals A mineral is a naturally occurring solid chemical substance that is formed through geological processes and that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not have a specific chemical composition or metal A metal is a chemical element that is a good conductor of both electricity and heat and forms cations and ionic bonds with non-metals. In chemistry, a metal is an element, compound, or alloy characterized by high electrical conductivity. In a metal, atoms readily lose electrons to form positive ions (cations). Those ions are surrounded by oxides. The latter term is generally used to refer solely to synthetic materials including fibreglass Fiberglass, , is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products; the resulting composite material, properly known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP), is called "fiberglass" in popular usage. Glassmakers throughout history have experimented, ceramic A ceramic is an inorganic, non-metallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous . Because most common ceramics are crystalline, the definition of ceramic is often restricted to inorganic crystalline materials, as opposed to the non- fibres and rock or stone wool. Industrial applications of mineral wool include thermal insulation The term thermal insulation can refer to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. Heat energy can be transferred by conduction, convection, radiation or by actual movement of material from one location to another. For the purposes of this discussion only the first three, filtration Filtration is a mechanical or physical operation which is used for the separation of solids from fluids by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the, soundproofing Soundproofing is any means of reducing the sound pressure with respect to a specified sound source and receptor . There are several basic approaches to reducing sound: increasing the distance between source and receiver, using noise barriers to block or absorb the energy of the sound waves, using damping structures such as sound baffles, or using, and germination of seedlings Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk.
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History
Slag wool was first made in 1840 in Wales by Edward Parry but the harmful effects on the workers caused production to be abandoned.[1] It was first produced commercially in 1871 at the Georgsmarienhütte Georgsmarienhütte is a town in the district of Osnabrück, in Lower Saxony, Germany. It is situated in the Teutoburg Forest, approx. 7 km south of Osnabrück in Osnabrück Osnabrück is a city in Lower Saxony, Germany, some 80 km NNE of Dortmund, 45 km NE of Münster, and some 100 km due west of Hannover. It lies in a valley penned between the Wiehengebirge and the northern tip of the Teutoburg Forest. As of June 30, 2006, its population was 163,357, making it the third-largest city in Lower Saxony Germany A region named Germania, inhabited by several Germanic peoples, has been known and documented before AD 100. Beginning in the 10th century, German territories formed a central part of the Holy Roman Empire, which lasted until 1806. During the 16th century, northern Germany became the centre of the Protestant Reformation. As a modern nation-state,.
Manufacture
Stone wool is a furnace product of molten rock Lava is molten rock expelled by a volcano during an eruption. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at temperatures from 700 °C to 1,200 °C . Up to 100,000 times as viscous as water, lava can flow great distances before at a temperature of about 1600 °C, through which a stream of air or steam is blown. More advanced production techniques are based on spinning molten rock on high speed spinning wheels A spinning wheel is a device for spinning thread or yarn from natural or synthetic fibers somewhat like the process used to prepare cotton candy Cotton candy , candy floss (British English), fairy floss (Australian English) is a form of spun sugar. Since it is mostly air, servings are large. Cotton candy is often served at fairgrounds or circuses. Food coloring is used to change the natural white color. A typical serving on a stick is at least one ounce and contains about 105 to 115. The final product is a mass of fine, intertwined fibres with a typical diameter of 6 to 10 micrometers. Mineral wool may contain a binder A binder is an ingredient used to bind together two or more other materials in mixtures. Its two principal properties are adhesion and cohesion, often food grade starch Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store. It is the most important carbohydrate in the human diet and is contained in such staple foods as potatoes, wheat, maize , rice, and cassava, and an oil Mineral oil or liquid petroleum is a by-product in the distillation of petroleum to produce gasoline and other petroleum based products from crude oil. It is a transparent, colorless oil composed mainly of alkanes and cyclic paraffins, related to petroleum jelly (also known as "white petrolatum"). It has a density of around 0.8 g/cm3 to reduce dusting Dust is a general name for solid particles with diameters less than 20 thou . Particles in the atmosphere arise from various sources such as soil dust lifted up by wind, volcanic eruptions, and pollution. Dust in homes, offices, and other human environments contains small amounts of plant pollen, human and animal hairs, textile fibers, paper.
Usage
Though the individual fibres conduct heat In heat transfer, conduction is the transfer of thermal energy between neighboring molecules in a substance due to a temperature gradient. It always takes place from a region of higher temperature to a region of lower temperature, and acts to equalize temperature differences. Conduction takes place in all forms of matter, viz. solids, liquids, very well, when pressed into rolls and sheets their ability to partition air makes them excellent heat insulators The term thermal insulation can refer to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. Heat energy can be transferred by conduction, convection, radiation or by actual movement of material from one location to another. For the purposes of this discussion only the first three and sound absorbers. Though not immune to the effects of a sufficiently hot fire, the fire resistance of fibreglass Fiberglass, , is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products; the resulting composite material, properly known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP), is called "fiberglass" in popular usage. Glassmakers throughout history have experimented, stone wool and ceramic A ceramic is an inorganic, non-metallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous . Because most common ceramics are crystalline, the definition of ceramic is often restricted to inorganic crystalline materials, as opposed to the non- fibres makes them common building materials Building material is any material which is used for a construction purpose. Many naturally occurring substances, such as clay, sand, wood and rocks, even twigs and leaves have been used to construct buildings. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The manufacture of building when passive fire protection Passive fire protection is an integral component of the three components of structural fire protection and fire safety in a building. PFP attempts to contain fires or slow the spread, through use of fire-resistant walls, floors, and doors (amongst other examples). PFP systems must comply with the associated Listing and approval use and compliance is required, being used as spray fireproofing Fireproofing, a passive fire protection measure, refers to the act of making materials or structures more resistant to fire, or to those materials themselves, or the act of applying such materials. Applying a certification listed fireproofing system to certain structures allows these to have a fire-resistance rating. The term fireproof does not, in stud cavities in drywall assemblies and as packing materials in firestops A firestop is a passive fire protection system of various components used to seal openings and joints in fire-resistance rated wall and/or floor assemblies, based on fire testing and certification listings.
Mineral wools are unattractive to rodents but will provide a structure for bacterial growth if allowed to become wet.
Other uses are in resin bonded panels, growth medium in hydroponics Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk, filler in compounds for gaskets, brake pads, in plastics in the automotive industry and as a filtering medium.
Mineral fibres are produced in the same way, without binder. The fibre as such is used as a raw material for its reinforcing purposes in various applications, such as friction materials, gaskets, plastics and coatings.
The heat that the material can withstand is:
| Material | Temperature |
|---|---|
| Glass wool | 230 - 250 °C |
| Stone wool | 700 - 850 °C |
| Ceramic fibre wool | 1200 °C |
In hydroponics
Mineral wool products can hold large quantities of water and air that aids root growth and nutrient uptake in hydroponics Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk; their fibrous nature also provides a good mechanical structure to hold the plant stable. The high natural pH In chemistry, pH is a measure of the acidity or basicity of a solution. It approximates but is not equal to p[H], the negative logarithm of the molar concentration of dissolved hydronium ions (H3O+); a low pH indicates a high concentration of hydronium ions, while a high pH indicates a low concentration. Crudely, this negative of the logarithm of mineral wool makes them initially unsuitable to plant growth and requires "conditioning" to produce a wool with an appropriate, stable pH.
Safety of material
Precautions need to be taken when handling a fibre product as it can be absorbed into the body by inhalation. It can also irritate the eyes Eyes are organs that detect light, and convert it to electro-chemical impulses in neurons. The simplest photoreceptors connect light to movement . In higher organisms complex neural pathways exist that connect the eye, via the optic nerve to the visual cortex and other areas of the brain. Complex optical systems with resolving power have come in, skin The skin is a soft outer covering of an animal, in particular a vertebrate. Other animal coverings such the arthropod exoskeleton or the seashell have different developmental origin, structure and chemical composition. The adjective cutaneous literally means "of the skin" . In mammals, the skin is the largest organ of the integumentary and respiratory tract In humans the respiratory tract is the part of the anatomy that has to do with the process of respiration. Prolonged exposure could lead to long term effects and it is considered a possible carcinogen A carcinogen is any substance, radionuclide or radiation, that is an agent directly involved in the exacerbation of cancer or in the increase of its propagation. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive substances are considered carcinogens, but their carcinogenic to humans, similar to asbestos Asbestos is a set of six naturally occurring silicate minerals exploited commercially for their desirable physical properties. They all have in common their asbestiform habit, long, (1:20) thin fibrous crystals. The inhalation of asbestos fibers can cause serious illnesses, including malignant lung cancer, mesothelioma (a formerly rare cancer. This effect may depend upon the fibre diameter and length, chemical composition and persistence within the body.
IARC The International Agency for Research on Cancer is an intergovernmental agency forming part of the World Health Organisation of the United Nations (the International Agency for Research on Cancer) has reviewed the carcinogenicity of man made mineral fibres in October 2002.[3] The IARC Monograph's working group concluded that only the more biopersistent materials remain classified by IARC as "possibly carcinogenic to humans" (Group 2B). These include refractory ceramic fibres, which are used industrially as insulation in high-temperature environments such as blast furnaces A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron, and certain special-purpose glass wools Glass wool is an insulating material, made from fibre glass, arranged into a texture similar to wool. Glass wool is produced in rolls or in slabs, with different thermal and mechanical properties not used as insulating materials. In contrast, the more commonly used vitreous fibre wools including insulation glass wool, rock (stone) wool and slag wool are considered "not classifiable as to carcinogenicity in humans" (Group 3).
High bio soluble fibres (HT-fibres) are produced that do not cause damage to the human cell. These newer biosoluble materials have been tested for carcinogenicity and most are found to be non-carcinogenic, or to cause tumours in experimental animals only under very restricted conditions of exposure. The IARC Monograph's working group "elected not to make an overall evaluation of the newly developed fibres designed to be less biopersistent such as the alkaline earth silicate or highalumina, low-silica wools. This decision was made in part because no human data were available, although such fibres that have been tested appear to have low carcinogenic potential in experimental animals, and because the Working Group had difficulty in categorizing these fibres into meaningful groups based on chemical composition."[4]
The EU risk and safety phrases associated with this material in general are:
- R38 – Irritating to the skin
- R39 – Danger of very serious irreversible effects
- R40 – Possible risk of irreversible effects
- S36/37 – Wear suitable protective clothing and gloves.
All European produced rock (stone) wool and glass wool is bio soluble and R39 and R40 do not apply. For these products only the risk phrase R38 remains. This irritation to the skin however is not a chemical irritation but only a temporal mechanical irritation, comparable with exposure of the skin to straw, grass or hay.
See also
References
- ^ Workshop Receipts, By Ernest Spon, Robert Haldane, Charles George Warnford Lock, Published by E. & F. N. Spon, 1889, Item notes: v.3
- ^ "Competition Commission Alternatives to Glass Mineral Wool". http://www.competition-commission.org.uk/inquiries/completed/2004/superglass/glass_wool_report.pdf. 090820 competition-commission.org.uk, 2.2 Mineral Wools
- ^ IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 81 (2002), Man-made Vitreous Fibres (PLEASE NOTE: Some manufacturers of insulation products have cited this volume while making erroneous claims that "IARC scientists confirm safety of mineral wool insulation". These claims are false. The findings in this volume are not a determination of non-carcinogenicity or overall safety.)
- ^ IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 81 (2002), Man-made Vitreous Fibres, Overall evaluation, p. 339
External links
| Wikimedia Commons has media related to: Thermal insulation |
- Rock Wool material safety data sheet A material safety data sheet is a form containing data regarding the properties of a particular substance. An important component of product stewardship and workplace safety, it is intended to provide workers and emergency personnel with procedures for handling or working with that substance in a safe manner, and includes information such as
- Thermal Insulation Association of Canada
- Master Insulators Association of Ontario
- Engineeringtoolbox.com treatise on mineral wool
- Canadianhomeworkshop.com Article: Know your insulation
- Statistics Canada documents on shipments of mineral wool in Canada
Categories: Materials | Building insulation materials
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Stephen Steiner
hu, 02 Apr 2009 00:01:35 GM
Energy-intensive refineries, for example, predominantly use . mineral wool. as an insulating medium. Silica aerogel materials are now poised to displace . mineral wool. as a superior insulation in the next decade, resulting in greater ...
