Energy From Thorium Discussion Forum

http://www.china.org.cn/business/2017-0 ... 997918.htm
The Chinese ADANES could use thorium like the ADS lt replaces. What could be the time frame of its wide acceptance?

ADANES is somewhat interesting from a design perspective compared to "conventional" Rubia style ADS...

Uses a windowless neutron spallation target design. The real trick here is rather than a straight up liquid metal (like lead or LBE) as the target, they are using helium cover gas SiC covered tungsten grains (0.5mm or less) as a target and heat transfer medium, which gives near-liquid properties (but also suffers from the some of the issues of larger ball pebble bed issues like dust) but they seem to have confidence in the flow of small grains. The grains appear to better handle proton beam trip transients, and no window means better overall system lifetimes. Not entirely clear how aggressive they are flowing the grains through the target area and back out, but they may be relying on hydrodynamic twister/entrainment effects of the grains to keep helium loss back through the beam pipe low.

Not sure where some of the efficiency claims are coming from though. These two PDF's seem to cover the main points decently enough. (PDF's too large to attach)

https://www.jaea.go.jp/news/symposium/RRW2016/shiryo/e07.pdf
http://indico2.riken.jp/indico/materialDisplay.py?materialId=slides&confId=1813

For a simple heat transfer medium, tungsten grains provide an interesting solution.

Why can't ADS systems simply using depleted uranium as the target?
That would seem to give maximum possible neutron multiplication.

Maybe deliberately avoiding nuclear materials as proton accelerator targets to back the "instant off" argument easily in front of the public? It can't be for lifetime reasons due to the neutron bombardment from the spallation target itself.