Reply to post: Re: Thorium Cycle Reactors

Boffins build blazing battery bonfire

Alan Brown Silver badge

Re: Thorium Cycle Reactors

"Why? Because they don't produce tasty isotopes of elements like Plutonium"


Very little plutonium has ever been weaponised from reprocessed civil reactors (other than to prove it's possible) as it's a mix of isotopes and some of them are "hot" enough to make any bombs "fizzle" instead of "boom" (paradoxically, nuclear weapons don't work well if the source materials are _too_ radioactive). Virtually all reprocessed plutonium gets mixed into civil fuel rods if its ever reused at all.

The weaponisation of uranium in the civil nuclear cycle happens when the uranium is enriched - a long time before any of it it ever sees the inside of a civil nuclear reactor.

Most is enriched to 3% and sold on to civil plants.

SOME is enriched well past 3% (usually to 50% or so) and used in military reactors to produce plutonium or in aircraft carrier/submarine reactors (which need to be smaller)

SOME of the leftover U238 ("depleted uranium") is used to make bullets.

U238 is an essential component of Teller-Ulam thermonuclear weapons (That's "hydrogen bombs" to you and me) - the casings are made out of it and MOST U238 gets used for this purpose.

Some U238 is onsold for paint pigment (it's yellow)

THIS is why the USA regards the costs of uranium enrichment for the civil nuclear program as a classified military secret - the power lines into the facilities in Tennessee show it's a huge energy consumer though.

This is why it's operated as a military project under the DOE, not a civilian one.

This is why enriching uranium anywhere in the world (even for civil reactors) is regarded as weapons manufacture - not because of the uranium, but because it can be used to make plutonium and THAT is what's used to make bombs.(U235 bombs are extremely expensive and require 95% enriched uranium)

The military hate Thorium cycle because it's extremely difficult to weaponise. The plutonium that's produced is an even more bastard mix of isotopes than in a uranium reactor and totally unusable (one of the Pu isotopes ia a very strong gamma emitter too). The Uranium isotopes are also a big mix.

Yes, you can extract U233 if you use a dual blanket system - but you'll pay for that with a massive reduction in power output, so it's noticeable - and the simple way to prevent this is to use a single fuel design.

This is why the "establishment" is so firmly wedded to using Uranium, despite its manifest UNsuitability for civil nuclear power generation - and will continue to be as long as there's a military mindset in charge. The cold war never really ended. The military machines got so large that their tail started wagging the dogs (countries) they were attached to a long time ago and they've been desperately trying to find an enemy (any enemy) to point at and distract the civilian population with for the last 25-30 years.

The public simply hate nuclear thanks to 70 years of scary stories,. "4 legs goood 2 legs baaaaad"

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