Areva - nuclear reactor technology

Areva -nuclear technology

Areva is a world leading company in nuclear energy . It is only company with presence each industrial activity liked to nuclear energy, mining , chemistry ,enrichment , combustibles, services, engineering nuclear population and reactors, treatment, recycling , stabilization and dismantling. Areva also claims to offer technological solutions for co2 free energy, and produces earth leakage circuit breaker technologies.

Four main subsidiaries of Areva
. Areva NP ( formerly Framatome ANP-nuclear power : develops and builds nuclear reactors Siemens has 34 per cent stake in Areva NP
. Areva NC ( formerly Cogema) nuclear cycle : covers the whole nuclear fuel cycle from mining to waste disposal
. Areva TA ( formerly Technicatome )  : develops and builds nuclear reactors and reactors for naval population .
. Areva T&D transmission and distribution  ;  It is in power transmission and distribution. It was bought from Alstom on 9th January 2004, currently Areva has entered  into exclusive negotiations with ALSTOM and Schneider Electronics for selling T&D drives .

Major partner of Areva include Euriware, STMicro electronics, Eramel  and Safron .

Areva is part of global energy partnership (GNEP)with Japan atomic energy agency (JAEA), Washington group international BMX. GNEP is plan initiated in 2006 for international partnership to reprocess spent fuel in a way that renders Plutonium in it usable for nuclear fuel but not for nuclear weapons.

European pressurized reactor EPR design

Frame tome (present Areva )and  Siemens in co-operation with E.D.F. and major German utilities  active since in 1992, in the development of European pressurized water reactor also known as Evolutionary pressurized water reactor (EPR).

Main objectives assigned to EPR were two fold. After a careful evolution of specific passive features, it was decided to design the EPR following an evolution approach  ; the advantage of funding an advanced design on operational from approximately 100 nuclear power plants. Constructed by Frame tome and Siemens was deemed by designs to be quiet important.

-As important as evolutionary feature was the objective to assure the competitiveness of nuclear power generation with any alternative energy sources . EPR was intended to provide significant improvement in terms of power generation cost as compared to most modern nuclear power plants and to large gas power plants with combined cycles.  To match this objective, a large unit power size was selected I.e. 1600MWe range.

Evolutionary design  : French and German safety authorities recommendations

In compliance with the rules established by French and German nuclear safety authorities for next generation of PWRs, and EPRs follows the following principals.

An evolutionary design to achieve maximum benefit from accumulated experience in designing and operating PWR units now in operation in France and Germany and in country’s where from Frame tome and Siemens exported their technologies (Belgium , Brazil ,China , Korea , South Africa , Spain, Switzerland ).  EPR design specially based on French N4 and German KONVOI experience.

An enhanced safety level .

 On the other hand ,decreased core melt probability has been achieved by improving availability of safety systems. On the other design features have been incorporated to limit radiological consequences in case of severe accident. For accidents without core melt, the architecture of peripheral buildings as well as the associated ventilation systems eliminate the necessity of protective measures for people living near damaged NPP unit. In the highly improbable but nevertheless envisaged situation of core melt accident at low pressure, the reinforced reactor building and specific palliative devices will limit radioactive releases. Only a few limited protective measures would be required. Lastly reactor design and confinement concept eliminate situations that could head to a large early releases.

With EPR  the probability of an accident leading to core melt, already extremely small with provision-generation reactors, becomes infinitesimal .

- Taking potential operating problems  into account very early  design effort, in depth work has been done during basic design phase to reduce to minimum collective personnel radiation exposure. Equipment maintenance  has been enhanced by good accessibility . Finally the human factor was integrated into the design to minimize the potential for human error in operation of EPR units.

Main design and operating data

Potential thermal NSSS power    from 4300 to 4600 Mwth
Rated electrical power          ------ 1650 MW(depend upon site conditions)

Reactor cooling system

Number of loop           --- 4
Operating pressure --------155 bars
Total flow/ loop     -------- 28000m3/ h
Main steam pressure ------ 78 bars

Core

Number of fuel assemblies ------- 241
Number of RCCA ------------------89
Fuel assembly array ---------------- 47X17
Active weight ------------------------420 cm

Areva lighter water reactor technologies

More than three quarters of fleet of nuclear power plants in operation across world used one of the two types of light water reactors.

Boiling water reactor (BWR)

On BWR the water is boiled and turn into steam inside vessel it self. Recirculation pumps force water that has not evoparized to return to the core, accelerating movement of natural circulation. The steam that is produced is transported directly turbine generator via steam pipe. Reactor containment prevent radio active products from dispersing in the event of damage to core.

. Areva has been active in the development of boiling water reactor (BWR) technology since early 1990 through its German subsidiary  Areva  GMBH.

. Areva offer a new 1250MWe boiling water reactor the “KERENA ‘ TM , it has developed at the request of German electric utilities in co-operation with other European countries . This generation 111 + reactor will provide the highest level of operation safety.

Pressurized water reactor (PWR)

In PWR a pressurized maintains the water at a pressure high enough to prevent it from boiling and kept in liquid form. This water referred to as primary coolant is not sent directly to the turbine. It circulates in a closed circuit between the core and the steam generator (SG) . This enables the heat from the&  uot primary coolant & uot to be transferred to the feed water which boils as its pressure is much lower. It is steam produced by feed water that is transported to the turbine generator .

PWR are most used across the globe (66 % of the current fleet in installed capacity) and equip the entire French nuclear power fleet. This biggest in world in terms of national electrical production (around 80 %) adopting single reactor give it a very homogeneous character . It benefits from continuous improvements   supported by the exceptional feed back of experience acquired by Areva from 58 reactors in operation.

. Areva therefore has 40 years of experience in the development of this reactor technologies and related services
. EPR  reactor developed by Areva is a 1650mwe  pressurized water reactor . This generation 111 reactor benefits from technological advances which makes it an advanced reactor . It provides increased level  competitiveness and safety while reducing impact on environment.

Areva signed agreement with India for setting up  1600 Mwe capacity   two European pressurized nuclear reactors for NPCIL (NUCLEAR POWER CORPORATION OF INDIA coming up Jaithapur  in Maharashtra state. Environmental approval has been given by environmental ministry recently.

However larger EPR built by AREVA yet see performance approval as non of its bigger EPR 1600 capacity in operation any where in world.