Hyperthermophilic Composting Technology for Organic Solid Waste Treatment: Recent Research Advances and Trends

Round 1

Reviewer 1 Report

Please improve the following areas:

1. There are several grammatical and syntax errors in the manuscript e.g., in abstract, authors wrote ".....could be applied to treatment organic solid waste...". It should be "treatment of" or "organic solid waste treatment". Please revise the manuscript carefully to avoid grammatical mistakes.
2. Authors stated in an introduction "To the best of our knowledge, little published papers have made comprehensive review about HTC". Please discuss how this review is different from reported reviews by other authors.
3. Section 2. Authors stated "Incineration was the most common method to treat solid waste around the world". It sounds that there is no more practice of incineration process. In following lines , authors stated "However, this technology was not environmental friendly and sustainable developed in view of some remarkable disadvantages....." which does  not make sense. Please improve.
4. Please cite the source of data presented in first 7 rows of Table 1.
5. Sec. 3.2. Please state the correct phylum name. Family Thermaceae comes under the phylum Deinococcus-Thermus.
6. Sec. 4.1. Please discuss the operational condition and the limitations of HTC project for cattle manure treatment.
7. Sec. 4.2. Please improve the discussion based on quantitative data of NOx. 
8. Please improve the Sec. 4.3, 4.4, and 4.5 emphasizing recent studies.
9. Future perspectives are not well discussed. Please improve.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

This paper reviewed the developments of hyperthermophilic composting (HTC) technology for the organic solid waste treatment. The basic principle, process flow, operation parameters, and applications of HTC were discussed. This work needs significant improvements before the consideration of publishing in Processes. 

The detailed review comments for this review article are as follows:

1. please change "Taiyuan, 030024" to "Taiyuan 030024".
2. The English writing in the whole paper needs careful revisions, such as "research and application advances" in Abstract (what did you mean research advances and application advances?); please do not use "What’s more" in Abstract; "Fig .1" changes to "Fig. 1"; "little published papers" in Introduction; etc. 
3. At the end of the Abstract, please add the future prospects of HTC technology to highlight the importance of this review.
4. In Keywords, please capitalize the first letter of all the phrases. 
5. For all the figures, have you obtained the copyrights of these figures such as Fig. 1?
6. In Introduction, for the production of sewage sludge, please provide the latest data after 2015. Since this is not a regional review, how is the status of the production of sewage sludge in other regions in the world? 
7. In Fig. 2, were these figures representative for the various occasions? Copyrights? The resolution of the figures should be improved.
8. In Table 1, for the data listed for HTC and TC, where did you cite these values?
9. In Section 3.2, why did the authors only list the Chinese authors' works?
10. Please improve the quality of the schematic in Fig. 3.
11. This review is only a summary of the Chinese works. The authors should review more papers worldwide and provide their own views toward this topic.
12. In Section 5, the implication and future perspectives were too short. 
13. Regarding the GHG emission, remediation of heavy metal-polluted soils and removal of MPs and antibiotic residues, what are the differences between HTC and TC?
14. In References, please review more papers and not only limited in Chinese authors' works.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Authors addressed all my comments and finely improved the manuscript. It can be published in current form.

Author Response

Thank you for your comments.

Reviewer 2 Report

I do not think that the authors have made significant improvements in the current paper.

As this is a review article, only 36 paper cited in the review? It should be at least 80-100 papers described in the review. Any results cited from the previous works as shown in a figure?

As mentioned earlier, 90% papers are cited from Chinese authors' work. What have you improved for the contents?

In Ref. 31, "Photographs. Available online: https://so.youku.com/(accessed on May.1, 2020)." -- Is this professional for a citation??? 

English writing is very poor. Any improvements from last round review? 

If the authors do not make significant improvements, I do not think that this paper can be accepted as a comprehensive review paper.

Author Response

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Author Response File: Author Response.pdf

Round 3

Reviewer 2 Report

Thanks for your efforts to improve the review article. However, for the low quality of the current paper, I do not think that the authors have revised the review article carefully and accordingly.

1. Regarding the first comment in second round of peer review, the authors just added the citations in the text without extending the manuscript. Please also discuss the details from some of these cited references. Please also avoid "lump sum references", such as XXXXX [1-5]; all references should be cited with detailed and specific description. 
2. Figure 1 has so many citations in this paper. ("waste and livestock manure [1,2,3](Figure 1),", "as shown in Figure 1 [5,17,18].", "Figure 1. The category and component of organic solid waste [29].")
3. Refs. [29] and [66] are still in a format of a website. How could the authors find these figures?
4. "In addition, DY bacteria, discovered by Tong Zhu from Northeastern University in China...(information obtained from communication with en-gineers)." -- Any citation for the work of Tong Zhu???
5. The format of the paper needs major improvements before the consideration of the publication in the journal. "Tang [68]," should be "Tang et al. [68],".
6. Please list the details of the improvements of the English writing in this paper in the response letter. A proof reading by a native English speaker should be conducted to improve both language and organization quality.  
7. "The features comparison between HTC and TC were showed in Table 1.“ -- ”were" should be "are".
8. The unit of the parameters should be unified such as m3·t-1·h-1, 
9. In Section 4, most of the presented works are from Chinese authors. How about the findings from other regions?
10. In Funding section, "No. 2019YFC0408601 and 2019YFC0408602" -- "Nos. 2019YFC0408601 and 2019YFC0408602".
11. It is better to show some previous results in the figures for the comparisons of the efficiency via different methods considering the effect of various influencing factors such as the temperature. 

Author Response

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Author Response File: Author Response.pdf