Effect of Coated Cow Dung on Fluidization Reduction of Fine Iron Ore particles
Round 1
Reviewer 1 Report
The paper by Qing-min Meng et al. investigates the optimal operating parameters which influence the process of fluidized reduction of iron particles. The authors examine the influence of coated cow dung on the reduction of iron particles, to improve the fluidization state through a non-trivial process involving the decomposition of hydrogen and consequent reaction with iron oxide.
The paper is well written, with good quality data and the elucidation of the inhibition mechanisms on particles adhesion is exhaustive. I propose to publish the paper after the authors have considered the following minor remarks:
- the results of the experiments, and in particular those shown in tables 8 and 9 and in figures 4 to 6, lack of the error bars. At least an estimate of the uncertainties should be needed; e.g. in figure 5 it is difficult to understand how significant are the differences among the sticking ratios for the different coating materials.
- in figure 6 different symbols should be used for the metallization rate and the sticking ratio.
- line 210: probably ‘see’ is a typo.
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1) Reviewer #“1(1). figures 4 to 6, lack of the error bars”
Response: Figure 4,5,6was modified in page8-9
Fig.4 comparison of metallization rates of different coating materials and contents
Fig.5 comparison of sticking ratio of different coating materials and contents
Fig.6 cow dung for Newman mine metallization rate and binder ratio affect the line chart change with content
2) Reviewer #1“(2) line 210: probably ‘see’ is a typo.”
Response: ‘see’ has been delete
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: 
Author Response.doc
Reviewer 2 Report
The manuscript seems to be interesting, but certain improvements and corrections are necessary.
1) Better explanation of the position of your research among other similar studies need to be presented in the Introduction. More works of other researchers dealing with research of "fluidization reduction of fine iron ore particles" are to be added. The application of the product and the necessity of the process need to be described in detail.
2) Lines 131-136: The space is usually left between the value and unit.
3) Table 4 seems to be redundant, because it is contains the same information like Table 5 and nothing more.
4) The origin of the values presented in Table 6 and Table 7 is not explained sufficiently; in particular, it is necessary to explain, why the average values of results, acquired at very different conditions, are determined and used for analyses. It seems to be somewhat unusual and incorrect processing of data (without detailed explanation).
5) Lines 152, 153: equation s=6 is divided by line break - typesetting error.
6) Lines 159-163: Omitted spaces between values and respective units; improper unit for temperature.
7) Lines 166-169: The last two sentences in the paragraph are somewhat unclear. It is not clear enough, what were "these conditions" used for preliminary experiments. Were they with gas or not?
8) The beginning of part 3.2.1. (172-177) repeats the already presented information.
9) Figures 4 and 5 seem to be redundant - information presented in Table 8 and Table 9 is sufficient.
10) To improve the soundness of the research the researchers are demanded to complete experiments for cow dung content between 10% and 20% with small step (e.g. 2%).
11) Typesetting error - title 3.1.2. is separated from the subsequent text by a page break.
12) Description of the measuring device presented in lines 216-219 and its settings is not correct - check it and improve it.
13) Lines 228-229: describe the "sample a" in detail - composition, etc.
14) Line 268: Improve English expression, it is unclear.
15) Line 282: Unclear expression "pressure drop drops sharply".
16) Information in lines 296-312 is similar to explanation presented in line 323-349: this text could be compound to summarize all presented information in one shorter paragraph.
17) Are Eq. 4-11 and Eq. 4-12, referred in lines 357 and 360 respectively, those ones presented as (14) and (15)?
18) Explanation presented in lines 361-367 and respective Fig. 11 need improvement, they are not sufficiently clear.
19) Line 401 - the expression "energy spectrum of cow dung with and without cow dung" is absurd.
20) Line 416: energy spectrum with and without cow dung - but energy spectrum of what?
21) Line 419: Figure label needs to be inseparably bound with respective figure.
22) Lines 420-456: The explanation of the processes and respective sketch presented in Fig. 14 is not sufficiently clear. Make the explanation shorter, more compact and clear (as well as the respective draws in Fig. 14).
23) Formal errors in Conclusion: line 472 - space between of and 923 is omitted; point (4) in in the improper font format.
24) There are many formal and factual errors in References:
a) numbers in this type of brackets [ ] are in the beginning of almost all referred publications;
b) references 9., 11., 20. seem to be just a part of references;
c) the sign [J] is uselessly implemented at the end of the article titles;
d) spaces between authors' names and initials are often omitted;
e) the shortening et al. is incorrectly used in the list of references, namely in lines 512, 514, 516, 519 - it is necessary to present all authors in the list of references.
Recommendation - the whole list of references thoroughly check and correct according to the MDPI standard.
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1) Reviewer #“2(1). Lines 131-136: The space is usually left between the value and unit.”.
Response: The “923K, 1023K ,1123K,20min, 40min, 60min,0.1MPa, 0.2MPa and 0.3MPa, 0.4m/s ,0.6m/S and 0.8m/s” has been changed to “923 K, 1023 K ,1123 K,20 min, 40 min, 60 min,0.1 MPa, 0.2 MPa and 0.3 MPa, 0.4 m/s ,0.6 m/S and 0.8 m/s”in article.
2) Reviewer #“2(2). Table 4 seems to be redundant, because it is contains the same information like Table 5 and nothing more.
Response: Table 4 is the orthogonal experimental scheme table, which is used to obtain the optimal operation parameters
3) Reviewer #“2(3). The origin of the values presented in Table 6 and Table 7 is not explained sufficiently”
Response: Table 6 and table 7 are a method of range analysis. The larger the range of which factor is, the greater the influence on the experimental results will be. Ki represents the sum of the test results for the corresponding level number in each column; ki = Ki/s where s is the number of times the level appears on any column, s =6 in this table; the range R indicates that it affects the Newman ore the primary and secondary of powder reduction are the maximum value of each factor level minus the minimum value, R = kmax-kmin. The larger the R value, the more obvious the reduction effect of this factor on Newman ore.
4) Reviewer #“2(4). Lines 152, 153: equation s =6 is divided by line break - typesetting error.”.
Response: “s =6 has been changed to s=6”
5) Reviewer #“2(5). Lines 159-163: Omitted spaces between values and respective units; improper unit for temperature.”.
Response: “1023k,60min,0.2Mpa,0.4m/s”have been changed to“1023 K,60 min,0.2 Mpa,0.4 m/s.”
6) Reviewer #“2(6). Lines 166-169: The last two sentences in the paragraph are somewhat unclear.”.
Response: Through the above experiment, we get an optimal experimental parameter condition, but in the orthogonal experiment scheme, reduction temperature of 1023 K, linear velocity of 0.6 m/s, reduction time of 60 min, reduction pressure of 0.2 MPa, and H2 as the reduction gas .we do not have this scheme, we do not get the corresponding experimental results under such conditions, so we need to do another set of experiments under the optimal operating parameters to get the corresponding metallization rate and sticking ratio.
7) Reviewer #“2(7). The beginning of part 3.2.1. (172-177) repeats the already presented information.”
Response: the sentence“Because the fluidization reduction is affected by many factors, previous research on fluidization reduction has examined the following factors: reduction time, reduction temperature, reduction gas linear velocity, coating composition.”has been delete.
8) Reviewer #“2(8). Typesetting error - title 3.1.2. is separated from the subsequent text by a page break.”
Response: the title“3.1.2 Effect of coated cow dung on phase structure.” has been changed to “3.2.2 Effect of coated cow dung on phase structure.”
9) Reviewer #“2(9). Description of the measuring device presented in lines 216-219 and its settings is not correct - check it and improve it”?
Response: XRD, Instrument model: D8ADVANCE, Manufacturer: German Brooke company. Main technical specifications:Target material: Cu Target; Power: 3kw; Scanning mode of goniometer: θ/θ Scanning range: -3 ~ 150 degrees; Accuracy of goniometer: 0.0001 degree; 2θ Angle accuracy: ≤ 0.02 degree.
10) Reviewer #“2(10). Line 282: Unclear expression "pressure drop drops sharply.”
Response: the sentence “so that the bed pressure drop drops sharply”has been changed to “so that the bed pressure drops sharply.”
11) Reviewer #“2(11). Are Eq. 4-11 and Eq. 4-12, referred in lines 357 and 360 respectively, those ones presented as (14) and (15)?
Response: “Eq. 4-11, Eq. 4-12”has been changed to“Eq (14) ,Eq (15)”
12) Reviewer #“2(12). Line 416: energy spectrum with and without cow dung - but energy spectrum of what?
Response: The content of elements in the sample can be analyzed by energy spectrum
13)Reviewer #“2(13) Line 419: Figure label needs to be inseparably bound with respective figure.
Response: Corresponding modifications have been made
14)Reviewer #“2(14) Formal errors in Conclusion: line 472 - space between of and 923 is omitted
Response: of923-1023 K has been changed to of 923-1023K
15)Reviewer #“2(15) the sign [J] is uselessly implemented at the end of the article titles;
Response: all the [J] have been deleted.
16)Reviewer #“2(16) spaces between authors' names and initials are often omitted;
Response: Corresponding modifications have been made
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: Author Response.doc
Reviewer 3 Report
The article is interesting for the research and development of ironmaking process using fluidized bed technology and interesting for readers. The authors conduct a series of experiment with clear explanations that makes the paper further interesting for readers. There are some minor comments that should be taken before publishing the article.
- In the abstract: The optimum velocity is mentioned as 0.6 m/s. The velocity does not give proper information without mentioning particle sizes in the fluidized bed. Therefore the particle size should be mentioned (although it is explained in the experimental section).
- Line 60 -Is there any reason to sieve dong to 0.154 mm? This should be explained for readers.
- Table 2, where does the chemical composition of dong comes from, ultimate, proximate analysis or literature data? This should clarified. Is there any limitation of moisture content?
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1)Reviewer #“3(1)the particle size should be mentioned (although it is explained in the experimental section).
Response: “fine iron Newman ore particles” has been changed to “fine iron Newman ore particles(0.154-0.178mm)”
2)Reviewer #“3(2) Is there any reason to sieve dong to 0.154 mm
Response: This can be done, we have the corresponding standard screen
3)Reviewer #“3(3) Table 2, where does the chemical composition of dong comes from, ultimate, proximate analysis or literature data? This should clarified. Is there any limitation of moisture content?
Response: The composition is based on the results of elemental analysis and references. The cow dung used is dried
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: Author Response.doc
Reviewer 4 Report
An interesting approach is presented in this work. This work will definitely find its readers. An innovative approach is used here. Adequate instruments and equipment were used for the research. The aim was to find the optimal properties that were achieved using the addition of 15% cow dung.
Some things need to be corrected and clarified.
Tables 4 and 5 could be combined into one.
Correct the font size in heading 3.1.
Part of the text on determining the optimal parameters is not entirely clear. (Chapter 3.1)
The calculation of Kki values is not entirely clear. To which table does it apply. What are the reasons for use. It would be good to describe this methodology a little more clearly.
Figure 6 seems unnecessary. Repeats the results in Figures 4 and 5.
Figure 8. Incorrect marking in the description of this figure.
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1)Reviewer #“4(1)Correct the font size in heading 3.1.”
Response: it has been modified
2)Reviewer #“4(2) The calculation of Kki values is not entirely clear.”
Response: This is a method to analyze the range. The range can reflect the influence of the influencing factors on the experimental results. The larger the range is, the greater the influence is
3)Reviewer #“4(3)Figure 6 seems unnecessary. Repeats the results in Figures 4 and 5.
Response: Figure 6 is a separate analysis of the impact of cow dung, a separate figure is to more directly reflect the results
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: Author Response.doc
Round 2
Reviewer 2 Report
Some corrections have been made, but it is necessary to check the whole manuscript and to correct improper expressions of physical units (e.g. MPa instead of Mpa, kW instead of kw, etc.). It is necessary to have space between the value and respective unit throughout the whole manuscript, not only in the parts, where the reviewers mentioned it.
I want the authors to explain two things that were pointed out in the previous review:
1) Why the Table 4 is not released - it is possible to comment the Table 5 in this way: Orthogonal experimental plan, experimental scheme and results. (Label of the contemporary Table 5 seems to be incomplete.)
2) Why the comment aimed at the more detail experiment around the extremes in the metallization rates and the sticking ratio "To improve the soundness of the research the researchers are demanded to complete experiments for cow dung content between 10% and 20% with small step (e.g. 2%)" was not responded?
The format of references still needs improvement according to Journal's standards. Moreover, there are some improper line breaks between lines 505 and 506, 507 and 508 or 523 and 524 (and maybe some others).
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1)Reviewer #“2(1) Why the Table 4 is not released - it is possible to comment the Table 5 in this way: Orthogonal experimental plan, experimental scheme and results..”
Response: Tables 4 and 5 have been merged and the title of cousin 5 has been changed to Orthogonal experimental scheme and results
2)Reviewer #“2(2) To improve the soundness of the research the researchers are demanded to complete experiments for cow dung content between 10% and 20% with small step (e.g. 2%)..”
Response: According to your suggestion, we added the following experiment. Thank you very much for your advice. We will consider more in future experiments.
table 10 effect of cow dung content on metallization rate and sticking ratio
|
Content index |
10% |
12% |
14% |
16% |
18% |
20% |
|
metallization rate |
76.95 |
80.84 |
85.78 |
91.35 |
84.12 |
80.78 |
|
sticking ratio |
26.83 |
24.32 |
21.63 |
20.02 |
24.68 |
28.62 |
3)Reviewer #“2(3) The format of references still needs improvement according to Journal's standards. Moreover, there are some improper line breaks between lines 505 and 506, 507 and 508 or 523 and 524
Response: References 8, 9 and 17, 18 have been modified accordingly
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: 
Author Response.pdf
Reviewer 4 Report
I cannot unequivocally recommend a modified version for publication.
The reason is insufficient resolution of ambiguities and errors based on the review recommendation.
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
2)Reviewer #“4(1) Tables 4 and 5 could be combined into one.
Response:Tables 4 and 5 have been merged and the title of cousin 5 has been changed to Orthogonal experimental scheme and results
2)Reviewer #“4(2)Correct the font size in heading 3.1.”
Response: font size has been modified
3)Reviewer #“4(3) The calculation of Kki values is not entirely clear.”
Response: This is a method to analyze the range. The range can reflect the influence of the influencing factors on the experimental results. The larger the range is, the greater the influence is
4)Reviewer #“4(4)Figure 6 seems unnecessary. Repeats the results in Figures 4 and 5.
Response: Figure 6 is a separate analysis of the impact of cow dung, a separate figure is to more directly reflect the results.
5)Reviewer #“4(5)Figure 8. Incorrect marking in the description of this figure.
Response: Figure 8 has been modified
Fig.8 SEM images of Newman ore after reduction ((a) and (b)without coated cow dung, (b) and (d)) with coated cow dung
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: Author Response.pdf
Round 3
Reviewer 2 Report
Some imperfections still persist:
e.g. Lines 52-53 - Table and 1 are separated by line break;
Lines 55-56 - the value and its unit are separated by line break;
Line 139 - Title 3.1 should start with capital letter;
Lines 14-141 - tables referred in text should start with capital letters, there is no space between 5 and "and" in line 141 and it is the redundant sign \ at the end of line 141;
Lines 154-155 - the value and unit are separated by line break;
Line 156 - there is no space between value and unit in 1023 K and the improper "k" is used as unit;
Line 157 - there are no spaces between respective values and units;
Line 172 - missing space between MgO and subsequent bracket as well as between particles and subsequent bracket;
Line 215 - the power should be 3 kW not 3kw
Section 4.2.2 (namely) - van der Waals is correctly Van der Waals (with capital V)
Line 357 - The expression "liftshitz van der Waals" should be Lifshitz - Van der Waals, as it is a constant of the Lifshitz theory of Van der Waals forces, sometimes called the macroscopic theory of Van der Waals forces?
Table 7 is missing now - it is necessary to shift the numbering of tables (also in text).
Throughout the whole manuscript the labels of Figures and Tables should start with capital letter of the respective figure or table and also the text after the number of figure/table should start with capital letter (example: Table 1. Number of neutrons in studied radioactive elements).
Some other imperfections could be in the manuscript - it is necessary to check it thoroughly.
Author Response
Dear editors and reviewers,
I am very grateful to your comments for the manuscript. Here below is our description on revision according to the reviewer’s comments and the changes in the manuscript within the document have been tracked by using the red colored text.
1)Reviewer #“2(1) e.g. Lines 52-53 - Table and 1 are separated by line break;”
Response: all tables are separated by line break.
2)Reviewer #“2(2) the value and its unit are separated by line break”
Response: “0.154-0.178mm” has been changed to“0.154-0.178 mm”
3)Reviewer #“2(3) Title 3.1 should start with capital letter”
Response:“3.1 optimum operating parameters” has been changed to“3.1 Optimum operating parameters”
4)Reviewer #“2(4) tables referred in text should start with capital letters, there is no space between 5 and "and" in line 141 and it is the redundant sign \ at the end of line 141”.
Response:“table 5and table 6” has been changed to“table 5 and table 6”.and sign \ at the end of line 141 has been deleted.
5)Reviewer #“2(5) there is no space between value and unit in 1023 K and the improper "k" is used as unit”
Response:“1023k”has been changed to“1023 K”
6)Reviewer #“2(6) there are no spaces between respective values and units”
Response: “20min，0.2MPa，0.6m/s” has been changed to“20 min，0.2 MPa，0.6 m/s”
7)Reviewer #“2(7)missing space between MgO and subsequent bracket as well as between particles and subsequent bracket”
Response:“MgO(density is 2940 kg/m3, with porous morphology), plastic particles(PP、PE etc.)”has been changed to “MgO(density is 2940 kg/m3, with porous morphology), plastic particles(PP、PE etc.) ”
8)Reviewer #“2(8)the power should be 3 kW not 3kw”
Response: 3 kw has been changed to 3 kW
9)Reviewer #“2(9)Section 4.2.2 (namely) - van der Waals is correctly Van der Waals (with capital V) ”
Response: all “van der Waals” have been changed to “Van der Waals” in Section 4.2.2
10)Reviewer #“2(10) The expression "liftshitz van der Waals" should be Lifshitz - Van der Waals”
Response: “liftshitz van der Waals” has been changed to Lifshitz - Van der Waals”
11)Reviewer #“2(11) Table 7 is missing now - it is necessary to shift the numbering of tables (also in text).”
Response: The sort of the table has been modified.
12)Reviewer #“2(12) Throughout the whole manuscript the labels of Figures and Tables should start with capital letter of the respective figure or table and also the text after the number of figure/table should start with capital letter.”
Response: All the charts have been capitalized.
Table 1 chemical composition (mass%) of Newman ore powder in Australia has been changed to Table 1 Chemical composition (mass%) of Newman ore powder in Australia;
Table 2 Chemical composition of cow dung (wt%) has been changed to Table 2 Chemical composition of cow dung (wt%);
Fig.2 experimental equipment has been changed to Fig.2 Experimental equipment;
Fig.3 experimental setup: (a) fluidized bed reactor (b) flow chart has been changed to Fig.3 Experimental setup: (a) fluidized bed reactor (b) flow chart;
Table 5 result analysis of metallization rate has been changed to Table 5 Result analysis of metallization rate;
Table 6 result analysis of sticking ratio has been changed to Table 6 Result analysis of sticking ratio;
Table 7 metallization rate of Newman ore with different coating materials and compositions has been changed to Table 7 Metallization rate of Newman ore with different coating materials and compositions;
Table 8 sticking ratio of Newman ore with different coating materials and compositions has been changed to Table 8 Sticking ratio of Newman ore with different coating materials and compositions;
Fig.4 comparison of metallization rates of different coating materials and contents has been changed to Fig.4 Comparison of metallization rates of different coating materials and contents;
Fig.5 comparison of sticking ratio of different coating materials and contents has been changed to Fig.5 Comparison of sticking ratio of different coating materials and contents;
Fig.6 cow dung for Newman mine metallization rate and binder ratio affect the line chart change with content has been changed to Fig.6 Cow dung for Newman mine metallization rate and binder ratio affect the line chart change with content;
Table 9 effect of cow dung content on metallization rate and sticking ratio has been changed to Table 9 Effect of cow dung content on metallization rate and sticking ratio;
Fig.9 bonding behavior diagram has been changed to Fig.9 Bonding behavior diagram;
Fig.11 schematic diagram of van der Waals force during coating process has been changed to Fig.11 Schematic diagram of van der Waals force during coating process;
Fig.12 energy spectrum with and without cow dung ((a) without cow dung (b) with cow dung) has been changed to Fig.12 Energy spectrum with and without cow dung ((a) without cow dung (b) with cow dung);
Fig.14 reduced iron ore powder particles and restraining mechanism schematic diagram has been changed to Fig.14 Reduced iron ore powder particles and restraining mechanism schematic diagram
Thank you and all the reviewers for the kind advice.
Sincerely yours，
Dr. Xu
Author Response File: Author Response.docx
Reviewer 4 Report
I have no further comments
