Ultimate Safe Reactor
Design Advantages of Molten Salt Reactors
There are a number of advantages a molten salt reactor design possesses as compared to a typical light water reactor. These are described in a paper by Uri Gat of ORNL.
Mr. Gat calls it the U.S. Reactor. I like that. Call it whatever you want; it does have significant advantages.
Of course, nuclear (almost exclusively comprised of light water reactors) is already the safest among the energy sources.
Alvin Weinberg, as I explained in a previous article was one of the inventors of light water reactors. He fell out of favor as the director of Oak Ridge National Lab (ORNL) when he kept pointing out that there were other inherently safe reactor designs, like molten salt reactors.
The U.S. reactor has two design features that would absolutely eliminate Chernobyl, Fukushima, and Three Mile Island accidents. (I might as well address the elephants in the room.)
The reactor is operated with no excess criticality, hence no criticality accident is reasonably possible.
Fission products are continuously removed at the rate they are produced, thus retaining the inherent source term at an insignificant level.
Chernobyl was an excess critically accident caused by intentional operator abuse. Physics prevents this from happening in the U.S. reactor.
The Fukushima reactors were damaged by the decay heat from fission products after the reactors were scrammed (fission of the nuclear fuel was stopped) when they sensed the earthquake. The resulting tsunami some ten minutes later destroyed the backup cooling systems, which led to partial core melting in three reactors and hydrogen gas build up and subsequent explosion (of the hydrogen gas). NO nuclear explosion did or could occur.
In the U.S. Reactor, decay heat producing fission products are removed continuously and stored in passively cooled containers. No human intervention is required to keep them cool.
Lastly, Three Mile Island Unit 2 was irreparably damaged (partially melted core) from decay heat after a series of mistakes involving cooling water, pumps, valves and operators.
The U. S. Reactor removes the decay heat producing fission products and stores them in passively cooled containers. Additionally, the entire fuel load of the reactor can be quickly drained (the fuel is liquid with viscosity approaching that of water) to passively cooled storage tanks. See below in red.
Other advantages of the U.S. reactor are:
I will discuss each briefly.
High negative temperature coefficient means that physics will control the nuclear reaction. If something perturbs the rate, the additional heat will cause the fuel salt to expand, which will slow the reaction.
The fuel is liquid, so those pretty little ceramic fuel pellets in the precise zirconium tubes and bundles are not needed. The liquid fuel does not swell with time due to the presence of fission products or radiation damage. This is a significant cost savings.
There is no water in the design and no need to keep the water at 2,000 to 5,000 psi to keep it from boiling at the reactor design temperatures. This eliminates vast amounts of structural steel in piping and vessels.
The salt fuel stays liquid (no phase changes) at reactor temperatures and atmospheric pressure and is immune to radiation damage because of its ionic bonds.
I’m sold on the U.S. reactor. Where can I buy one? Can I get some federal income tax credit for investing in a U.S. reactor?