Nuclear waste

munky99999

From what I know the Nuclear waste that we have now. It gets burried and cemented into dead mines.

Well as there is also a problem that the synthetic plastics do not decompose in landfills for a long time.

Is it possible that we could use the radiation from the waste to break up the bonds of the plastic polymers?

Astronuc

The disposal on nuclear (or radioactive) waste depends on the country. In the US, there are compacts or arrangements between groups of states for disposal of low-level nuclear waste. See - http://www.ag.ohio-state.edu/~rer/rerhtml/rer_61.html and http://www.nei.org/doc.asp?catnum=3&catid=303

The waste, encased in steel drums, is buried in a land-fill. Handford site and Barnwell (South Carolina) are two such sites. See - http://www.downwinders.org/llw_facts.htm

http://web.em.doe.gov/idb97/chap4.html

High level waste (HLW, e.g. irradiated pressure vessels) is also buried, encased in some material. See - http://www.oversight.state.id.us/waste/highlevelwaste/

The DOE has a separate facility (WIPP, or Waste Isolation Project) near Carlsbad, New Mexico to deal with HLW from the DOE and weapons program.

Then there is the spent fuel from commercial nuclear reactors, which is currently stored in wet storage (spent fuel pool) or dry storage (casks) in an ISFSI. see http://www.nrc.gov/reading-rm/doc-co...res/br0216/r2/

In Japan - http://www.enecho.meti.go.jp/english.../disposal.html


Plastics would most likely be limited to low level waste. Radiation would not be signifiant, but as for plastics, it would produce some disintegration and perhaps cross-linking making the plastic brittle. Off-hand, I am not aware of any research into the disposition of long-term storage of plastic in LLW or HLW.

hypatia

I have heard that back in the 1990's europe{what countries I don't recall} began to fuse the waste with glass, then covered in steel and buried. There was some talk that it also will happen here in the US.
The advantage of course would be no worry of liquid leaking.
Anyone hear of this?

Astronuc

The process is called 'vitrification' and yes some countries have done, particularly France and Britain in their reprocessing programs. The fission products are vitrified.

Waste vitrification plant (WVP)

Japan is receiving vitrified waste from the European reprocessors as part of their MOX program - Japanese Waste and MOX Shipments From Europe

There was some work done in the US at the West Valley Plant (near Buffalo, NY) and at the Savannah River Site (Aiken, SC).

Nomy-the wanderer

I know that there's some of the world's nuclear waste burried in the western desert here in Egypt..Which is threatening cause people started to use it as farms, also there r many natural water resources there. Not sure where it is exactly, but some people were heavily paid for that.

hypatia

This vitrification seems reasonable to me, is there any major drawbacks to it?
The plants themselfs seem to have some problems, hopefully they have worked out the kinks by now...?

hitssquad

The current installed power reactor generation is Generation II. Generation III, which has received final approval in the United States and which is currently being installed in other nations, is a refinement of the Generation II reactors with safety, efficiency, and streamlined construction being the primary design goals. If nuclear power is expanded soon in the United States, it will be with reactors that are far safer than the 103 reactors currently installed there.

If you have any questions regarding nuclear safety, you can have them expertly answered here:
http://groups.yahoo.com/group/Know_Nukes

hypatia

I'm sorry, I should of been more clear, tho power plant safety is always a plus. I live with in eye sight of Fermi 2.
I meant the vitrification plants, which in the article says they are only at 35%. But then saw where the story was several years old.

Astronuc

I posted the article on Sellafield in order to provide some idea of the technology. The process was introduced well after the reprocessing program. Same problem in the US. The weapons program produced tons of high level radioactive waste which accumulated in storage tanks at Savannah River and Hanford sites, and IIRC INEL. There have been major 'cleanup' program since the 1980's to deal with the waste - some of which involve vitrification. Savannah River is a relatively recent project.

With regard to commercial programs, the US suspended recycling in the late 1970's during the Carter administration. At the time, there was the West Valley Project, and limited reprocessing was performed.

A 1995 reference U.S.-German Cooperation in Elimination of Excess Weapons Plutonium (1995), WPu Disposition Through Vitrification with HLW, C.1 TECHNOLOGY discusses the background of vitrificiation as of 1995: "Today that vitrification process is well advanced and is considered to be suitable to convert high-level waste, and in particular high-level liquid waste (HLLW) into a stabilized waste form. The technology has been developed and practiced for over 20 years. There are plants in operation worldwide, including those in Sellafield, The Hague, Mol, Marcoule, Chelyabinsk, and Tokai-Mura, and the U.S. facility at Savannah River is expected to begin operation in 1996."

Under current practice, commercial spent fuel is not reprocessed, but the goal is direct disposal in a repository (Yucca Mountain). Currently, spent fuel assemblies are stored in spent fuel pools at the reactor site, or if sufficiently old, the fuel is stored in dry storage systems - until (or rather if and whenever) the US government takes title to the fuel, transports it, and perhaps places it in the (final?) repository.

Morbius

http://www.srs.gov/general/about/history1.htm

Dr. Gregory Greenman
Physicist

hypatia

Wow, they have come a long way. Thank-you for all the information and great site links.

dx/dy=?

High level waste can boil at extremely high temp's for many years after its fission activation, and needs to be "stirred" at regular intervals to prevent critical temperatures affecting the storage-containers, hence the need for waste-pools.

This basically means only low-level waste is viable for vitrification.

Even then, materials such as thorium will continue to undergo nucleic-decay, decomposing into materials such as lead.
Exothermic reactions such as these can easily crack and fracture glass, as glass has no finite ionic-bound, or crystalline lattice structure.

This is still leading to problems in storing radioactive materials in vitric suspension.

Astronuc

An alternative to vitrification using a 'glass' base is the use of Synroc - or synthetic rock - which has been around for 20+ years.

Synroc

hitssquad

Instead of Synroc I think we can just say "ceramics in general", Astronuc.

Two immobilization options:

1. glassification
2. ceramization

Astronuc

Agreed.

It's been a long time since I looked at Synroc, but as I remember it, the argument was that the Synroc material was 'more thermodynamically stable', and it attempted to replicate those naturally occurring minerals which have remained essentially chemically inert or otherwise unchanged for millions of years.

Hundreds of thousands of years would be sufficient to allow the radionuclides to decay to inert isotopes. Even the most radioactive materials are decayed in years, decades or centuries, which then leaves the longest half-life nuclides, which consequently have lower specific activity, to decay in an inert matrix.

hitssquad

Oops. My unabridged dictionary says "glassification" is not a word. I wish it was. I was using that because whenever I say, "vitrification," people ask me what that means. These 3,820 folks use it, though:

google.com/search?q=glassification