Tuesday, September 10, 2013

A blueprint for fast-tracking Thorium Reactor programme in India

A blueprint for fast-tracking Thorium Reactor programme in India 



The thorium reactors can be rapidly commissioned in India with little or no modification to the existing reactors used to produce electricity.

I suggest that Nuclear Corporation of India and BHAVINI be given the responsibility to activate the use of thorium fuel cycle in four selected reactors for this thorium reactor programme which can be achieved in the next 4 to 6 months.

This should be independent of and complementary to the 3-stage nuclear programme of the country. The objective to achieve production of 2/3rd electricity from thorium fuel in the selected reactors.

A separate Thorium division should be set up in DAE to work with NCI and BHAVINI to carry forward the time-bound programme, to demonstrate to the world the technological competence of Indian nuclear scientists for leadership role in the use of thorium fuel cycle.

Thorium division of DAE should be charged with the responsibility to evaluate alternative design options for further augmentation of the thorium reactors in the country using alternatives such as Molten Salt breeder reactors (MSBRs) whose efficiencies have been proven. The Thorium Division of DAE should also explore avenues for collaboration and cooperation with the countries of Indian Ocean Community to share the technologies possessed by Indian scientists in the areas of nuclear fuel fabrication, nuclear reactors, nuclear power generation and space technology.

Framework for the thorium nuclear reactors of India

Thorium cycles are feasible in all existing thermal and fast reactors, e.g., Pressurized Heavy Water Reactors (PHWRs), Liquid Metal cooled fast breeder reactor (LWRs)[including WWERs especially Light-water Thorium Reactor (WWER--T)], High temperature gas cooled reactors(HTGRs), Molten Salt breeder reactors (MSBRs) and in Accelerator Driven System (ADS).

It should be possible to incorporate the thorium cycle in some of the existing reactors without major modifications in the engineered systems, reactor control and the reactivity devices. (IAEA, 2005, p.5)
It is possible to ininerate weapons-grade plutonium (WPu) in combination with thorium in light-water reactors of WWER-1000 type type to burn and not breeed 239Pu. For this, mixed thorium plutonioum oxide, containing ~~5% PuO2, could be used as driver fuel. The exclusion of uranium from fuel composition results in an essential increase in the rate of plutonium incineration compared to the use of standard mixed uranium plutonium oxide (MOX) fuel. The spent mixed thorium plutonioum oxide on achieving the standard burnup (~~40 MW days/kg HM) of LWR fuel is not only degraded in terms of WPu content but also becomes 'proliferation-resistance' with the formation of 232U, which has very strong gamma emitting daughter products. (IAEA, 2005, p.10)

The stock of civil plutonium could be significantly decreased by using the same in combination with thorium in WWER-1000 type reactors. A direct replacemet of low enriched uranium oxide fuel is possible by mixed thorium plutonium oxide fuel without any major modifications of core and reactor operation. In such a reactor, there is no need to use burnable absorber in the form of gadolinium, integrated into the fuel. The 240Pu isotope, present in significant quantities in civilian grade plutonium, is a good burnable absorber. (IAEA, 2005, p.11)

Both weapons Pu and civilian Pu could be efficiently disposed in combination with thorium as mixed throium plutonium oxide containing 20 to 30% PuO2 in commercial LMFBRs. In small LMFBR cores, like the demonstration type FBTR in India, the PuO2 content in (Th,Pu)O2 fuel could be much higher and in the range of 70 to 80%. (IAEA, 2005, p.11)

To overcome the constraints imposed by Nuclear Suppliers' Group for supply of uranium/plutonium to India -- even despite the Indo-US Nuclear Deal -- the plutonium/uranium released from the throium nuclear reactors can be augment the needs of Fast Breeder Reactor Programmes under the 3-stage nuclear programme of India.

The goal to be achieved is thus simple, feasible and dramatic. Two-third nuclear power production from thorium nuclear reactors will come from thorium fuel, using India's indigenous thorium reserves, thus conserving scarce uranium/plutoniums nuclear fuels.

 http://www-pub.iaea.org/mtcd/publications/pdf/te_1450_web.pdf

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