Reviewer 2: minor comments

[andrewryh]

Abstract

• [x] Considering the scope of the journal, mentioning the names of companies and start-up is not appropriate. I would suggest removing them.

Introduction

• [x] The sentence "Immediate advantages over traditional, solid-fueled, reactors include near-atmospheric pressure in the 15 primary loop, relatively high coolant temperature, outstanding neutron economy, improved safety parameters," may suggest improved neutron economy vs solid-fuel fast reactors. This is rarely the case, especially vs Pu-based SFRs. I would suggest reformulating.

• [x] The sentence "With regard to the nuclear fuel cycle, the thorium cycle produces a reduced quantity of plutonium and minor actinides (MAs) compared to the traditional uranium fuel cycle" is correct, but the fact that this is an advantage is questionable. The pros&cons of thorium cycle have been long debated and there is no consensus on its advantage in terms of exposure of workers, exposure of public, geological repository, etc. I would suggest removing the sentence.

• [x] "Methods listed in references [14, 17, 24, 25, 28, 29, 30] as well as the current work also employ a batch-wise approach". As a matter of fact, the work in [14] allows for continuous reprocessing via introduction of "reprocessing" time constants. The work from Aufiero (mentioned in the following paragraph) actually used the methodology previously developed in [14] for verification purposes.

• [x] Table 3. It is not clear what "effective cycle times" are. Please clarify.

• [x] The removal of fission products is made batch wise in the described algorithms. However it is not clear how the fission products with the longest "effective cycle times" are removed. Part of them at every batch? Or all of them at the end of the "effective cycle times". Please clarify. And please clarify the relation between "effective cycle times", batches and the average time spent by a fission product in the reactor.

• [x] The oscillatory behavior shown in Fig. 7 on the time scale of months/years is hard to explain. Is this because the fission product with longer residence time are batch-wise removed at their "effective cycle time"? In case, why not to remove part of them at every depletion step?

• [x] "This thorium consumption rate is in good agreement with a recent online reprocessing study by ORNL [29]." Please notice that in a reactor with only Th as feed, and near equilibrium, the Th consumption rate is exclusively determined by the reactor power and by the energy released per fission.

• [x] Are you considering the effect of the gradual poisoning of the graphite with fission products? If not, it would be worthwhile briefly discussing its effect.

• [x] "The current work results show that a true equilibrium composition cannot exist but balance between strong absorber accumulation and new fissile material production can be achieved to keep the reactor critical." Not clear. Do you mean that the equilibrium composition cannot be achieved in a lifetime of the reactor? Please clarify

[andrewryh]

And please clarify the relation between "effective cycle times", batches and the average time spent by a fission product in the reactor.

Help needed here.

[andrewryh]

Please notice that in a reactor with only Th as feed, and near equilibrium, the Th consumption rate is exclusively determined by the reactor power and by the energy released per fission.

I cannot agree with Reviewer 2 here. It also determined by neutron spectrum. I will add this note in the conclusion section.