The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Hydrogen-Rich Gas: A Study of Cases

Round 1

Reviewer 1 Report

The paper presents a review of the pig iron production using the mini blast furnace process and of the ‘green’ process development ideas.

The title and the intentions declared in the abstract correspond to the contents of the paper. The paper contains abstract and introduction which is in fact a critical review of the state of the art. The authors have contributions in the field of the pig iron production using the mini blast furnace process.

I found to many similarities with other paper from the same authors published also in 2020. The title of the paper is "A Comprehensive Modeling as a Tool for Developing New Mini Blast Furnace Technologies Based on Biomass and Hydrogen Operation" and was published in Journal of Sustainable Metallurgy, 2020.

The text from lines 55 to 116 is almost identical to the text presented in the above-mentioned paper at pages 1-2 (Introduction). Please change this text.

• In abstract there are two times ii); the last one should be iii).
• Lines 98 and 114, please add the word „process”, i.e. „mini blast furnace process”, since the mini blast furnace is just the equipment
• Line 144, Table 1, not Table1
• Line 173, In “Thus, an useful analysis code to predict the integrated value in use of the new raw materials to introduce in the green pig iron production route” seems that lacks the verb. May be a good idea to rephrase the sentence.
• To increase clarity, the explanations in lines 207-216 should be placed either before equation 1, or immediately after equation 7.
• Line 528 – I assume the link will be updated to reflect the actual address?
• A reviewing of the text from the point of view of the English language would be helpful to eliminate small, but sometimes important mistakes.
  • Line 184 „applied”, not „aplied”
  • Lines 320-321 ”all the carbon sources used in this mini blast furnace process are renewable ones”
  • Line 322 ”widen”, not ”wider”
  • Line 325 ”facility”, not ”facilities” – or remove the ”a”
  • Line 408 ”injection”

Overall Recommendation: Accept after minor revision

English language and style: Minor English changes required

Author Response

The authors are thankful to the reviewers and editors for the valuable comments and corrections on the manuscript. We addressed all the concerns and suggestions pointed out and carried out a grammatical and Language revision in the entire manuscript. We apologize for the mistakes in the last version. We hope this revision mitigates technical and communication shortcomings.

In the following paragraphs, we detail the reviewer's specific comments, and the authors reply to the modifications carried out in the manuscript.

Reviewer 1

Author's replies to the reviewer's comments and mandatory changes.

Open Review

(x) I would not like to sign my review report 
( ) I would like to sign my review report 

English Language and style

( ) Extensive editing of English Language and style required 
( ) Moderate English changes required 
(x) English language and style are fine/minor spell check required 
( ) I don't feel qualified to judge about the English Language and style 

Comments and Suggestions for Authors

Reviewer:

“The paper presents a review of the pig iron production using the mini blast furnace process and of the 'green' process development ideas.”

“The title and the intentions declared in the abstract correspond to the contents of the paper. The paper contains abstract and introduction which is in fact a critical review of the state of the art. The authors have contributions in the field of the pig iron production using the mini blast furnace process.”

“I found to many similarities with other paper from the same authors published also in 2020. The title of the paper is "A Comprehensive Modeling as a Tool for Developing New Mini Blast Furnace Technologies Based on Biomass and Hydrogen Operation" and was published in Journal of Sustainable Metallurgy, 2020.”

Authors answer: Indeed, the text was modified to differ from the previous one. The introduction was rewritten, and the Language's mistakes were fixed with the help of a native English colleague.

Reviewer:

“The text from lines 55 to 116 is almost identical to the text presented in the above-mentioned paper at pages 1-2 (Introduction). Please change this text.”

 Authors answer: Thank you. This part of the manuscript was rewritten.

• In abstract there are two times ii); the last one should be iii).

Authors answer: Sorry, it was a mistake. We fixed it.

• Lines 98 and 114, please add the word "process", i.e. "mini blast furnace process", since the mini blast furnace is just the equipment

Authors answer: Thank you for the correction.

• Line 144, Table 1, not Table1

Authors answer:

• Line 173, In "Thus, an useful analysis code to predict the integrated value in use of the new raw materials to introduce in the green pig iron production route" seems that lacks the verb. May be a good idea to rephrase the sentence.

Authors answer: This phrase was rewritten.

• To increase clarity, the explanations in lines 207-216 should be placed either before equation 1, or immediately after equation 7.

Authors answer: Ok. We placed just after equation 7.

• Line 528 – I assume the link will be updated to reflect the actual address?

Authors answer: Yes, the files and link will be furnished to appears at the online version.

• A reviewing of the text from the point of view of the English Language would be helpful to eliminate small, but sometimes important mistakes.

Authors answer: Ok. We asked help for the manuscript language check.

• Line 184 "applied", not "aplied"

Authors answer: Sorry. Fixed.

• Lines 320-321" all the carbon sources used in this mini blast furnace process are renewable ones"

Authors answer: We rewrite this phrase.

• Line 322" widen", not" wider"

Authors answer: Sorry. Fixed.

• Line 325" facility", not" facilities" – or remove the" a"

Authors answer: Sorry. Fixed.

• Line 408" injection"

 Authors answer: Sorry. Fixed.

Overall Recommendation: Accept after minor revision

English language and style: Minor English changes required

 Authors answer: Thank you very much. We checked the entire manuscript.

Reviewer 2 Report

The presented manuscript is an interesting and important contribution to the charcoal based ironmaking in mini blast furnaces. The presented further development of the model and simulation results is in general worth a publication.

However, the manuscript in its current form has serious problems and shortcommings.

First of all: This paper is not a review but a research paper! Please adjust the paper category and title accordingly.

Secondly: The paper is very close in content to another publication of the authors (ref [4]) with a series of overlaps. This goes so far that completely identical paragraphs can be found (see below). This requires a major revision of the manuscript, before a publication can be considered.

In general, there are some repetitions so that the text as a whole could be formulated much more stringent and concise.

In linguistic terms, the paper must be significantly improved by proofreading, e.g. by a native speaker. The necessary linguistic changes to the manuscript are too numerous to list them all here!

The followings points should be specifically adressed in a revised version:

line 25: it should go i), ii), iii) not two times ii) I assume.

Fig. 1a) includes green and gray lumps which are not explained in the legend.

Fig. 1 b): What is the meaning of the different colour of the arrows? What is the meaning of the different colours of the phases (green and yellow)?

Several paragraphs (e.g. 217-230, 247-258) are copy and paste from the ref. [4]

The beginning of section 3 (lines 297-334) belongs in section 2 since this is not about results but about materials and methods. Also, a table giving an overview over the modelled cases and their parameter sets is missing. 

Table 3: The composition of the injected gas is not explained but only given in the table. Where does this gas come from? Is it recycled top gas with some form of enrichment? Which "green" gas is used for the enrichment leading to high CH4 concentrations?

Lines 382-384: Even if some hydrogen enriched gas is injected into the BF, this process is still mainly carbon-based! bio-C is still C!

Section 3.2 & 3.3: without more detailed information about what has been changed between cases 1-20 (at least percentage changes of parameters between cases) it is not possible to comprehend results or reasoning of the authors.

Line 489: "several studies" are mentioned, so references should be given.

Section 4 again is almost a complete copy and paste of the according section in ref [4].

Author Response

Reviewer 2

Author's rebuttal letter and replies.

The authors are thankful to the reviewers and editors for the valuable comments and corrections on the manuscript. We addressed all the concerns and suggestions pointed out and carried out a grammatical and Language revision in the entire manuscript. We apologize for the mistakes in the last version. We hope this revision mitigates technical and communication shortcomings.

In the following paragraphs, we detail the reviewer's specific comments, and the authors reply to the modifications carried out in the manuscript.

Comments and Suggestions for Authors

The presented manuscript is an interesting and important contribution to the charcoal based ironmaking in mini blast furnaces. The presented further development of the model and simulation results is in general worth a publication.

However, the manuscript in its current form has serious problems and shortcommings.

First of all: This paper is not a review but a research paper! Please adjust the paper category and title accordingly.

Authors reply: The reviewer 1 did not agreed in this point. Thus, we left to the editors to decide in which category the paper is to be placed.

Secondly: The paper is very close in content to another publication of the authors (ref [4]) with a series of overlaps. This goes so far that completely identical paragraphs can be found (see below). This requires a major revision of the manuscript, before a publication can be considered.

Authors reply: We agree. The parts which were coincident were rewritten.

In general, there are some repetitions so that the text as a whole could be formulated much more stringent and concise.

In linguistic terms, the paper must be significantly improved by proofreading, e.g. by a native speaker. The necessary linguistic changes to the manuscript are too numerous to list them all here!

Authors reply: The paper was entirely revised. We hope the language mistakes and conciseness were improved. The specific points listed by the reviewers were fixed.

The followings points should be specifically adressed in a revised version:

line 25: it should go i), ii), iii) not two times ii) I assume.

Authors reply: sure, we fixed.

Fig. 1a) includes green and gray lumps which are not explained in the legend.

Fig. 1 b): What is the meaning of the different colour of the arrows? What is the meaning of the different colours of the phases (green and yellow)?

Authors reply: We explain in the caption of the figures and in the manuscript.

Several paragraphs (e.g. 217-230, 247-258) are copy and paste from the ref. [4]

The beginning of section 3 (lines 297-334) belongs in section 2 since this is not about results but about materials and methods. Also, a table giving an overview over the modelled cases and their parameter sets is missing. 

Authors reply: Ok we change this part.

Table 3: The composition of the injected gas is not explained but only given in the table. Where does this gas come from? Is it recycled top gas with some form of enrichment? Which "green" gas is used for the enrichment leading to high CH4 concentrations?

Authors reply: Ok we explain the source of the injecting materials in the manuscript.

Lines 382-384: Even if some hydrogen enriched gas is injected into the BF, this process is still mainly carbon-based! bio-C is still C!

Authors reply: Sure, this phrase was rewritten.

Section 3.2 & 3.3: without more detailed information about what has been changed between cases 1-20 (at least percentage changes of parameters between cases) it is not possible to comprehend results or reasoning of the authors.

Line 489: "several studies" are mentioned, so references should be given.

Section 4 again is almost a complete copy and paste of the according section in ref [4].

Authors reply: This section was completely rewritten.

Cordially

The authors.

Round 2

Reviewer 2 Report

The quality of the paper improved significantly. It can be published in the current state as a research article. However, this can not be published as a review paper, because it is not a comprehensive review but a presentation of research work of the authors.

According to the "Instructions for Authors":

• Reviews: These provide concise and precise updates on the latest progress made in a given area of research. Systematic reviews should follow the PRISMA guidelines.

So as a review I would have to vote for "reject". As a research article it can be published.

Author Response

Dear editors and reviewers. We are following the revised version of the paper with the changes, as requested.

The reviewer indicated that the paper could be accepted as an Article and not a Review. We agreed with the reviewer and make changes accordingly.

Line 1: Review changed to Article

The title of the paper: Lines 2-4

The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Rich-Hydrogen Gas: A Review

Changed to:

The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Rich-Hydrogen Gas: Study of Cases

Author Response File: Author Response.pdf