Areva - Reference Document 2016

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GLOSSARIES
1. Technical glossary
> Fuel cycle
The combination of industrial operations involving nuclear fuel. These operations
include uranium ore mining and processing, uranium conversion and enrichment,
fuel fabrication, used fuel treatment, recycling of recovered fissile materials to
fabricate new fuel, and radioactive waste management. The cycle is said to be
“open” when it does not include the recycling of the used fuel, considered as waste
to be sent directly to disposal following use in the reactor. Conversely, the fuel cycle
is said to be “closed” when it includes used fuel treatment and recycling of fissile
materials recovered by such treatment.
> Fuel rod
Sealedmetal tube made of a zirconium-based alloy measuring about 4meters long
(about 13 feet) and 1 centimeter in diameter (2/5 of an inch) and filled with about
300 pellets of nuclear fuel. The tube is known as cladding.
> Fundamental safety rules (Règles fondamentales de sûreté ,
RFS)
Rules designed to clarify the conditions with which compliance, for the specific
type of facility under consideration and for its purpose, is deemed to constitute
compliance with French regulatory practice.
> Gaseous diffusion
Process for the isotopic separation of molecular species that uses the difference
in the velocity of diffusion of these molecules (related to their different mass), and
thus the different rates at which they pass through a semi-permeable membrane.
The uranium hexafluorides 235UF6 and 238UF6 can be separated in this way, causing
enrichment in 235 U, the fissile isotope of uranium, for nuclear fuel.
> Gear box
The operating concept of wind turbines involves converting the kinetic energy
produced by the rotor at slow rotations of around 5 to 15 RPM into electrical energy
that is directly supplied to the grid at a frequency of 50 Hz.
The conventional design of wind turbines is based on the use of proven quadripole
electrical generators and requires an input speed of 1,500 RPM. A gear box is
necessary to adapt the rotor rotation speed to the generator while transmitting
energy. A gear box consisting of one or more simple or epicycloidal gear trains is
needed to transmit effort while adapting rotation speed.
Hybrid transmission wind turbines such as the AREVA M5000 are based on a
multipolar generator (some 40 poles) requiring much lower reduction ratios which
are affordable and thus allow the use of much more compact gear boxes.
Direct transmission wind turbines use heavily multipolar generators that are costlier
but eliminate the gear box stage completely.
> General operating rules ( Règles générales d’exploitation,
RGE)
Document describing the operating rules (règles générales d’exploitation, RGE)
defined for the facility and identifying items important for safety. It describes
measures to be taken if facility performance is outside the normal operating mode.
> General radiation protection rules
Document containing rules (règles generals de radioprotection, RGR) describing the
combination of measures taken to protect people and prevent the risk of exposure
to radiation.
> Generation IV reactor
An innovative reactor system or reactor type that could go on line by the 2040
to 2050 timeframe. These reactor systems are being designed in the framework
of international cooperation known as the Generation IV International Forum, in
which France is participating. The systems aim to respond to the need to reduce
waste volumes, conserve resources, and ensure greater safety and reliability in the
nuclear reactors of the future.
> Glove box
A transparent enclosure in which equipment or materials can be handled in isolation
from the operator. Handling is done with gloves attached in leak-proof manner
to openings in the wall of the enclosure or with mechanical manipulators. The
enclosure is generally kept at slightly negative pressure to contain radioactive
materials.
> HCTISN (Senior committee for transparency and
information on nuclear safety)
A body for information, consultation and discussion of the risks related to nuclear
operations and their impact on public health, the environment and nuclear
security. As such, it may issue opinions on any matter in these fields, as well as
on related oversight and information. It can also examine any matter pertaining to
the accessibility of information on nuclear safety and recommend any measure to
ensure or improve transparency in nuclear matters.
> Heat recovery
Heat recovery power plants use the residual heat from industrial processes to
generate electricity. The technology consists of transferring heat to a heat recovery
boiler to producemore heat and electricity via a steam turbine. Heat recovery power
plants can reduce demand for energy from industrial facilities and therefore reduce
their CO 2 emissions.
> Heavy metal
Heavy metal is the nuclear material in fuel: uranium and possibly plutonium in the
case of MOX fuel. The unit of measurement commonly used for heavy metal is the
metric ton of heavy metal (MTHM).
> HFDS (Senior defense and security official)
The French Defense Code tasks the Minister of Energy with the control of civilian
nuclear materials. To date, due to the current division of powers within the French
government, that responsibility has been shared by the Minister of Economy,
Finance and Industry and the Minister of Environment, Energy and Oceans. To
carry out these responsibilities, the Ministers rely on the Defense, Security and
Economic Intelligence Service and its employees in charge of examining cases and
drafting regulations. The service answers to the Senior Defense and Security Official
(HFDS), who acts as the nuclear safety authority for the Minister of Environment,
Energy and Oceans.
2016 AREVA REFERENCE DOCUMENT 375