Magnox Ltd

Magnox Ltd is a nuclear decommissioning Site Licence Company (SLC) controlled by Cavendish Fluor Partnership, its designated Parent Body Organisation (PBO). It operates under contract for the Nuclear Decommissioning Authority, a government body set up specifically to deal with the nuclear legacy under the Energy Act 2004.

Magnox Ltd is responsible for the decommissioning of ten Magnox nuclear power stations in the United Kingdom. The ten sites are Berkeley, Bradwell, Chapelcross, Dungeness A, Hinkley Point A, Hunterston A, Oldbury, Sizewell A, Trawsfynydd and Wylfa. All the sites have ceased production. In addition, as part of the Trawsfynydd unit, Magnox Ltd operates a hydro-electric power station at Maentwrog.

The only Magnox power station in the UK not managed by Magnox Ltd is Calder Hall, which is part of the Sellafield site and is controlled by another SLC, Sellafield Ltd.

History

Magnox Ltd is the successor company to Magnox Electric, which was created in 1996 to take ownership of the Magnox assets from 'Nuclear Electric' and 'Scottish Nuclear'. The remaining nuclear power stations of these two companies, seven advanced gas-cooled reactor (AGR) sites and one pressurized water reactor (PWR) site, were transferred to a separate company, 'British Energy', which was then privatised in 1996. In January 1998 Magnox Electric came under the control of another government-owned company, 'British Nuclear Fuels', operating as 'BNFL Magnox Generation'.

Magnox

Magnox is a now-obsolete type of nuclear power reactor, which was designed in the United Kingdom and was exported to other countries, both as a power plant and, when operated accordingly, as a producer of plutonium for nuclear weapons. The name magnox comes from the magnesium-aluminium alloy used to clad the fuel rods inside the reactor.

General description

Magnox reactors are pressurised, carbon dioxide cooled, graphite moderated reactors using natural uranium (i.e., unenriched) as fuel and magnox alloy as fuel cladding. Boron-steel control rods were used. The design was continuously refined, and very few units are identical. Early reactors have steel pressure vessels, while later units (Oldbury and Wylfa) are of prestressed concrete; some are cylindrical in design, but most are spherical. Working pressure varies from 6.9 to 19.35 bar for the steel pressure vessels, and the two prestressed concrete designs operated at 24.8 and 27 bar. No British construction company at the time was large enough to build all the power stations, so various competing consortia were involved, adding to the differences between the stations; for example nearly every power station used a different design of Magnox fuel element.

Magnox (alloy)

Magnox is an alloy—mainly of magnesium with small amounts of aluminium and other metals—used in cladding unenriched uranium metal fuel with a non-oxidising covering to contain fission products in nuclear reactors. Magnox is short for Magnesium non-oxidising. This material has the advantage of a low neutron capture cross section, but has two major disadvantages:

The magnox alloy Al80 has a composition of 0.8% aluminium and 0.004% beryllium.

See also

References

Magnox (disambiguation)

Magnox can refer to:

Private company limited by shares

A private company limited by shares, usually called a private limited company (Ltd.) (though this can theoretically also refer to a private company limited by guarantee), is the private limited type of company incorporated under the laws of England and Wales, Scotland, that of certain Commonwealth countries and the Republic of Ireland. It has shareholders with limited liability and its shares may not be offered to the general public, unlike those of a public limited company (plc).

"Limited by shares" means that the company has shareholders, and that the liability of the shareholders to creditors of the company is limited to the capital originally invested, i.e. the nominal value of the shares and any premium paid in return for the issue of the shares by the company. A shareholder's personal assets are thereby protected in the event of the company's insolvency, but money invested in the company will be lost.

A limited company may be "private" or "public". A private limited company's disclosure requirements are lighter, but for this reason its shares may not be offered to the general public (and therefore cannot be traded on a public stock exchange). This is the major distinguishing feature between a private limited company and a public limited company. Most companies, particularly small companies, are private.

LTD

LTD, Ltd, or Ltd. may refer to:

Business and finance

Music

Science and technology

Transportation

Other uses

Leukotriene D4

Leukotriene D4 (LTD4) is one of the leukotrienes. Its function main in the body is to induce the contraction of smooth muscle, resulting in bronchoconstriction and vasoconstriction. It also increases vascular permeability. LTD-4 is released by basophils. Other leukotrienes that function in a similar manner are leukotrienes C4 and E4. Pharmacological agents that inhibit the function of these leukotrienes are leukotriene receptor antagonists (e.g. Zafirlukast, montelukast) and are useful for asthmatic individuals.

References