Feolite is a type of
iron oxide
Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of w ...
sintered
Clinker nodules produced by sintering
Sintering or frittage is the process of compacting and forming a solid mass of material by pressure or heat without melting it to the point of liquefaction.
Sintering happens as part of a manufacturing ...
into
building blocks, which are then used for
heat
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is ...
storage.
Feolite was developed in
Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
.
[
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Characteristics
Feolite, one of many materials used for heat storage, being a solid, does not have any volumetric or pressure containment issues, but correspondingly does require the use of a transfer medium to then get the stored heat to the desired location.specific heat
In thermodynamics, the specific heat capacity (symbol ) of a substance is the heat capacity of a sample of the substance divided by the mass of the sample, also sometimes referred to as massic heat capacity. Informally, it is the amount of he ...
of feolite is 920.0 J·kg−1·°C−1,density
Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematicall ...
is 3,900 kg·m−3, and its thermal conductivity
The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by k, \lambda, or \kappa.
Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal ...
is 2.1 W·m−1·°C−1.[
]
History
Feolite was invented in 1969 by Electricity Association Technology, then called Electricity Council Research Centre.trademark
A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies products or services from a particular source and distinguishes them from oth ...
in Australia for all iron oxides for use in the manufacture of thermal storage units which has now lapsed, by Electricity Association Technology of the United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
.[A sample of commercial systems from around the world:
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Application
Blocks of feolite enclosing sheathed electric heating elements to form a heat storage core, surrounded by thermal insulation, are used in storage heaters and storage radiators.rolling stock
The term rolling stock in the rail transport industry refers to railway vehicles, including both powered and unpowered vehicles: for example, locomotives, freight and passenger cars (or coaches), and non-revenue cars. Passenger vehicles can ...
.
Notes
References
{{Reflist
Energy storage
Heating, ventilation, and air conditioning