ADSCMSR (Accelerator Driven Sub-Critical Molten Salt Reactor)
What is an ADSCMSR?
The idea for this Accelerator-Driven Sub-Critical Molten Salt Reactor (ADSCMSR), as it is known, has been sitting on nuclear physicists’ drawing-boards for the past 20 years. The reactor has some high-profile fans, including Nobel Prize winner Carlo Rubbia, ex-director general of Cern. International firm Jacobs Engineering is developing its own version of the technology.
The ADSCMSR uses a particle accelerator to help generate the neutron that thorium must acquire to become fissile.
The accelerator drives a high-energy proton beam into a lead target embedded in the centre of a nuclear reactor filled with thorium. As the protons slam into the lead, neutrons are chipped off and convert thorium in the reactor to uranium-233. Depending on the target material, each proton can chip off about 30 neutrons, and it is these same neutrons that trigger fission in the uranium-233. With this type of a reactor you don’t need a chain reaction like in other reactors.
Without a nuclear chain reaction to control, operators could effectively switch off the reactor by flicking the switch that shuts off the proton accelerator. Shutdown would not be instant – fission would continue and decay heat from the radioactive products produced in the process would remain, but non-invasive control of the reactor would be possible.
How does an ADSCMSR Work?
Of the 3 options for creating energy from thorium (solid fuel in conventional reactors, liquid fuel in molten-salt reactors, or fuel in accelerator driven subcritical reactors), Stuart Henderson of Fermilab explores the accelerator driven approach.