Name: The first nuclear era
ISBN: 9781563963582

The first nuclear era

The First Nuclear Era is Alvin Weinberg's autobiography, the memoirs of a most influential American nuclear engineer/physicist. These reminiscences date from the dawning of the nuclear age in the early 1940s to the present. It is the story of one notable scientist's life and times and a look back at one of humankind's most ambitious endeavors: the attempt to harness and safely distribute nuclear power. Weinberg has witnessed and played a major part in many of the defining scientific moments of his era. Here he describes his academic career at the University of Chicago, under the tutelage of Nicolas Rashevsky and Carl Eckart. He recalls his wartime days at the Manhattan Project's Chicago Metallurgical Laboratory where he helped Nobelist Eugene Wigner design the Hanford plutonium producing reactors. He then focuses on what would become the abiding legacy of his professional life: his development of and involvement with nuclear reactors. In discussing both great commercial successes (such as the Light-Water Reactor) and unsuccessful experiments, Weinberg offers an objective critique of the technical and political shortcomings that have haunted the nuclear age. He also demonstrates how the lessons learned from unsuccessful reactors paved the way for later triumphs.

What Hacker News says

acidburnNSAJul 2019

MSRE had fans blowing on pipes as cooling. It had no real fluid-to-fluid heat exchanger or power conversion cycle, which is where lots of maintenance troubles arise from. Furthermore, they were in the 1960s, before the NRC existed and before we worried about ALARA. Furthermore, MSRE cannot to this day account for about half of their radioiodine inventory. Furthermore, Alvin Weinberg himself says in his 1990s autobiography, The First Nuclear Era (amazing read btw) that they were just piping radioactive gas into the forest nearby back then (or, wait, was that the aqueous homogeneous reactor? I forget, I left all my copies of that book at the office...).

A lot has changed since MSRE ran, and MSRE was a fairly simple experiment to prove a concept. It didn't have all the systems necessary to make practical energy, and so it didn't have the maintenance issues you'd expect. Also, it only ran for like 5 years, vs the 60-80 we're hoping for these days from these facilities (inherently requires lots of maintenance).

Have you ever done work planning for ALARA at a light water reactor? Those who have raise eyebrows really high when academic reactor designers start saying how easy the maintenance will be. Admiral Rickover's quotes from 1953 just keep on coming back to haunt us [1]. He didn't curse us to death, but he sure warned us that we need to be working really hard on new/effective solutions to these kinds of problems. Most advanced nuclear advocates skip over these points.

RE: Design it carefully: This takes practical experience. The number of people today designing new reactors who have this kind of experience is very close to zero. We will have to re-learn.

[1] https://en.wikiquote.org/wiki/Hyman_G._Rickover#Paper_Reacto...

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phasetransitionSep 2011

--Providing HN the details about Thorium that the Forbes article lacks--

tl;dr - Read Dr. Alvin Weinberg's book from the late 1990s. Amazon link here: http://www.amazon.com/First-Nuclear-Era-Times-Technological/...

-Background- I discovered liquid fueled nuclear reactors, and the thorium subset thereof, as a consequence of the chemistry minor I undertook in grad school at Georgia Tech (my background is materials engineering). One of the classes I took was taught by Dr. Jiri Janata, and it was functionally a class in analytical radiochemistry. Dr. Janata's expertise is in chemical sensors, and he worked for an number of years at Pacific Northwest National Lab (PNNL) on methods to detect the spread of radiation in the environment. Dr. Janata exposed our class to the liquid fueled reactors.

-LFR- To read in Dr. Weinberg's book, Oak Ridge was left out in the cold when it came to reactor design. This despite the fact that Weinberg and Eugene Wigner wrote "The Physical Theory of Neutron Reactors," as the definitive first text on reactor physics. Wigner and Weinberg dreamed up many dozens of potential power reactor design concepts in the 40s.

Oak Ridge National Lab managed to procure funding to pursue reactors that might power airplanes. Weinberg is candid about how the concept of nuclear powered flight was nearly fiction, but any grant in a storm! Any grant in a storm is still alive and well, btw.

Out of that work came the liquid fueled reactors, of which thorium could be one of the fuels. The liquids were composed of multi-component molten halide salt solutions that had some partial solubility for certain radionuclide salts. Much of the molten salt chemistry details we have today come as consequence of the research into their behavior from Oak Ridge.

Liquid fuels for reactors have many advantages: 1. They operate at atmospheric pressure (1 atm), so there's no pressure vessel to worry about bursting in an accident. 2. Molten salts have very little vapor pressure, and therefore don't volatilize as readily. 3. The molten salts allow very high operational temperatures for better Carnot efficiency, in part because of 2. 4. The systems is single phase, liquid only. This is in contrast to 2-phase behavior of something like BWR reactors 5. Waste fission products (e.g. iodine) can be scrubbed from the molten fuel during operation. The fuel composition can be monitored and changed as needed during operation. 6. Neutron reflectors are needed to obtain criticality in the system. The molten salt with nuclear material in it is subcritical by nature.

For a liquid fuel reactor, there is no loss of coolant accident, as the fuel is in the working fluid. The amount of decay heat from fission products remaining in the fuel can be lower if there would be scrubbing in place. As the world sees now, decay heat is the tiger in the room for reactor safety.

-Brief Accident Scenario- If an accident occurs, and power is lost, the molten fuel drains back into a core sump vessel which then is cooled to deal with the decay heat. Because the fuel is dispersed, and there are no high pressures to deal with, passive cooling of the decay heat in the molten fuel sump is greatly simplified. Further, natural convection can be stimulated in the sump to help circulate the fuel and remove heat.

-Follow Up(?)- There are some downsides, of course, but this is already crazy long. If the OP is still around in the morning on the East Coast, I'll discuss some of the negatives in another comment.

-phil

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carapaceJan 2021

I've heard that, I don't buy it. I think we are just stupid and crazy.

Biodegradable plastic has been a thing for over half a century yet the whole planet is choking on discarded plastic. Where's the sane reason for that?

Cars!

Cars aren't sane, we had to convince ourselves that they were though a deliberate campaign of domestic propaganda![1] Cars kill hella people (I don't have stats for the rest of the world but more Americans have been killed by cars than have died in all the wars we've fought!) And that's just the people that get hit. There's air pollution (car exhaust is a deadly poison) and tires are constantly wearing down and giving off vulcanized rubber particles. I won't deny their convenience, but you'll never convince we they're sane.

Or my old pet peeve: refrigerators. They open like cabinets instead of like drawers. The cold air goes out, the warm air goes in, and you get to pay for the energy to cool it off. Why not make them like a chest of drawers?

Sanity? I think not.

[1] "The Real Reason Jaywalking Is A Crime" (Adam Ruins Everything) https://www.youtube.com/watch?v=vxopfjXkArM)

Replying here to the other fella:

> The vaneless ion generator is >5x less efficient.

C'mon, less efficient by what metrics? Total cost over the lifetime of the structure, including maintenance? Killing eagles?

In re: Molten Salt reactors there's a old page[1] about Molten Salt tech in general that talks about reactors towards the end:

> The second MSR was a civilian power plant prototype, the Molten Salt Reactor Experiment (MSRE)7. Hugely successful, it was ignored by the US Atomic Energy Commission (US AEC), which had decided to favor the Liquid Metal Fast Breeder Reactor (LMFBR). The Director of ORNL, Dr. Alvin Weinberg, pushed for the MSR, but was fired for his efforts 8.

> 8. Pages 198 - 200, "The First Nuclear Era : The Life and Times of a Technological Fixer", by Alvin Martin Weinberg (1994).

I've read a longer history of Molten Salt reactors that described the events referenced in the above quote. Evidently both kinds of reactor showed promise early on (MS and LMFB) but for bureaucratic reasons the one was passed over for the other.

[1] https://web.archive.org/web/20040602210408/http://home.earth...

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