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You left out using the neutrons bled off through a Beryllium pipe and
fed to a Liquid Boron -10 Hydride (Borane) thrust nozzle
for "Fission Drive" spacecraft propulsion.
Neutron + Boron-10 (~ 10,500 Barns) + Hx ----> He4 + Li-7 + Hx =3.4 MeV (Propellents)
Specific Impulse from the reaction nozzle. Better than an Ion Drive for the long haul.
Fred
Edited for Brevity. :-)
----- Original Message -----
Sent: 11/3/05 11:27:21 AM
Subject: Re: Small Nuclear Power Reactors
Some time ago Jed Rothwell posted the original message:
"All kinds of interesting stuff has been added to this UIC web site lately. It is impressive. Almost too impressive; I fear they might succeed and hold back the development of CF! Main index:
http://www.uic.com.au/nip.htm
My preferred source for robust neutrons is/was a small aqueous homogeneous reactor (basketball-sized) using heavy water and a small amount of dissolved uranium nitride. Here you have a $50,000 replacement for a $500 million mile-long accelerator. Yes, you will need several for comparative purposes - as we are talking about smaller, modular units rather than a single large complicated plant.
There is no cheaper way to produce them in a fairly intense flux (10^12 per cm^3) than in the homogeneous reactor. It is super-safe even if it does require a few kilograms of highly enriched fuel. There are ways to eliminate the proliferation risk of this. The larger-reactor itself is a breeder, and with ongoing partial-reprocessing, so that the initial loading of both the homogeneous core and the much larger natural U blanket is sufficient for a 50 year life. It is not that there is no refueling - there is in fact continuous refueling and reprocessing. But the difference !
is that all the fuel which is needed for 50 years is included at the outset. Burnup is 90%. All waste which is not removed in the minimal ongoing reprocessing, is burned in situ.
With a cheap source of "makeup" neutrons - to be employed in smallish, mass-produced rail-mounted subcritical reactor of about 50 MW each, fueled by natural uranium - there is a lot of borrowing of other concepts... so there is similarity here to the CANDU or newer ACR700 - which designs are a pressurized plumbing nightmare, and do not get the full benefit of an extremely "cheap" source of neutrons - although the worst kept secret in nuclear engineering is that there is a huge anomaly in how many "free" neutrons one gets from a deuterium moderator.
Jones
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