السبت، 30 يوليو، 2011

مشاهدة فيلم مشاهدة فيلم صرخة نملة dvd اون لاين dvd اون لاين

مشاهدة فيلم مشاهدة فيلم  صرخة نملة dvd اون لاين dvd اون لاين

Enrichment will be up to 6% U-235, and reprocessed uranium will only be handled in the second, north unit. There is potential to expand capacity to 11 million SWU/yr, probably with a third unit.
When fully operational in 2018 the whole SET plant will free up some 3000 MWe of Tricastin nuclear power plant's capacity for the French grid - over 20 billion kWh/yr (@ 4 c/kWh this is EUR 800 million/yr). The new enrichment plant investment is equivalent to buying new power capacity @ EUR 1000/kW.  The GB II plant will require only about 75 MWe (80 kWh/SWU, compared with about 2600 kWh/SWU for GB I).
About 7300 tonnes of depleted uranium tails is produced annually, most of which is stored for use in Generation IV fast reactors. Only 100-150 tonnes per year is used in MOX. By 2040 this resources is expected to total some 450,000 tonnes of DU.
Enrichment of depleted uranium tails has been undertaken in Russia, at Novouralsk and Zelenogorsk. Some 33,000 tonnes of French DU from Areva and EdF has been sent to Russia in 128 shipments over 2006-09, and about 3090 t of enriched 'natural' uranium (about 0.7% U-235) has been returned as of May 2010: 2400 t to Eurodif, 380 t to Areva Pierrelatte, and 310 t to Areva FBFC Romans. The contracts for this work end in 2010, and the last shipment was in July 2010 with the returned material to be shipped by year end. Tails from re-enrichment remain in Russia as the property of the enrichers.
Fuel fabrication is at several Areva plants in France and Belgium. Significant upgrading of these plants forms part of Areva's strategy for strengthening its front end facilities.  MOX fuel fabrication is described below.
Fuel cycle - back end
France chose the closed fuel cycle at the very beginning of its nuclear program, involving reprocessing used fuel so as to recover uranium and plutonium for re-use and to reduce the volume of high-level wastes for disposal. Recycling allows 30% more energy to be extracted from the original uranium and leads to a great reduction in the amount of wastes to be disposed of. Overall the closed fuel cycle cost is assessed as comparable with that for direct disposal of used fuel, and preserves a resource which may become more valuable in the future. Back end services are carried out by Areva NC.  Used fuel storage in pools at reactor sites is relatively brief, and no dry storage is used.
Used fuel from the French reactors and from otehr countries is sent to Areva NC's La Hague plant in Normandy for reprocessing. This has the capacity to reprocess up to 1700 tonnes per year of used fuel in the UP2 and UP3 facilities.  The treatment extracts 99.9% of the plutonium and uranium for recycling, leaving 3% of the used fuel material as high-level wastes which are vitrified and stored there for later disposal. Typical input today is 3.7% enriched used fuel from PWR and BWR reactors with burn-up to 45 GWd/t, after cooling for four years.  In 2009 Areva reprocessed 929 tonnes, most from EdF but 79 t from SOGIN in Italy. By 2015 it aims for throughput of 1500 t/yr.
EdF has been sending some 850 tonnes for reprocessing out of about 1200 tonnes of used fuel discharged per year, though from 2010 it will send 1050 t. The rest is preserved for later reprocessing to provide the plutonium required for the start-up of Generation IV reactors. Reprocessing is undertaken a few years after discharge, following some cooling. Some 8.5 tonnes of plutonium and 810 tonnes of reprocessed uranium (RepU) are recovered each year from the 850 tonnes treated each year to 2009. The plutonium is immediately shipped to the 195 t/yr Melox plant near Marcoule for prompt fabrication into about 100 tonnes of mixed-oxide (MOX) fuel, which is used in 20 of EdF's 900 MWe reactors.  Four more are being licensed to use MOX fuel.

ليست هناك تعليقات:

إرسال تعليق