Experimental Study on Hydrogen Recombination Characteristics of a Passive Autocatalytic Recombiner during Spray Operation

Round 1

Reviewer 1 Report

The article is well written and addresses an important topic related to PAR performance under spray operation. Nevertheless, details are missing and need to be added to improve the readability of the article. These details are related to:

• page7: please justify the fact that the gas velocity at the outlet is the same as at the inlet
• page 7: in equation (5), Wh2 and Wm need to defined 
• page 8: equation 7 need to be revised.
• Page 8: the sentence related to Mh2,vessel at t is independant from its value at t-1, need to be rephrased at the value at t include the value at t-1
• p13: please check if the reason of the increase of the PAR exit gas temperature before the PAR catalyst is due to the thermocouple inside the catalytic module is wet 
• P19: please modify the conclusion accordingly  

Author Response

We deeply appreciate your effort to review the paper submitted to “hydrogen (hydrogen-1701222).

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The article (Manuscript Number hydrogen-1701222) describes the crucial author's advances concerning the hydrogen removal characteristics of a grid-type passive autocatalytic recombiners (PAR), that were experimentally evaluated when a pressure control system of spray was operated. What is most important is the aspect of accident management of a nuclear power plant in operation, the spray system may be activated before the release of hydrogen in the containment building. As the authors stated, since wetting of the PAR catalysts increases the delay time of the start-up of the PARs, it is necessary to review the effect of the PAR start-up delay by a spray operation on the containment hydrogen safety.
Generally, the article is very interesting, innovative, and written in a style that allows you to easily and quickly read what the author (authors) wanted to convey. In my opinion, this article include also a balanced, comprehensive, and critical view of the research area. These articles are not randomly selected articles in a literature review and are meticulously selected and thought out.
On the whole, the manuscript is well-written, and English is also on a good level. The overall originality of the concept used here is high. I would recommend the publication of this paper in Hydrogen as-is.  

Author Response

We deeply appreciate your effort to review the paper submitted to “hydrogen (hydrogen-1701222).

Reviewer 3 Report

The manuscript presents an interesting study about the evaluation of hydrogen recombination characteristics of a passive autocatalytic recombiner by a spray operation. The paper needs major revisions before it is processed further, some comments follow:

Abstract

Please highlight the novelty of the study. Add a short description of the test methods and write the most important conclusion.

 Introduction section

The introduction section must be improved.

Multiple citations have been introduced in bulk form "[1,2,3]", "[11,12,13]” , "[20.21,22,23]” etc. and not distributed in the text.

Subsections 4.2 and 4.3.

The authors present the results with very limited discussion. Please improve and introduce more comments about the obtained results.

Conclusion

The conclusion section is too long. The conclusions can be written by points with highlights.

Author Response

We deeply appreciate your effort to review the paper submitted to “hydrogen (hydrogen-1701222).

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

The author addressed all of my comments. The manuscript can be published in the present form. 

Author Response

We appreciate your effort to review the paper.