Study on the Properties of Vanadium Pellets Extracted from Vanadium Titanium Magnetite Concentrate by Calcium Roasting and Acid Leaching

Round 1

Reviewer 1 Report

This study has carried out the calcification roasting and acid leaching of vanadium-titanium magnetite to extract vanadium pellets, in which the effect of pelletizing, roasting and acid leaching on pellet performance and vanadium leaching rate was studied. The research work is full and the technical route is novel, which has a certain guiding role for industrial production. However, the following issues need to be explained before the article is accepted.

1. The abstract should be reorganized. The purpose or aim of this study should be given and it is better to present the results concisely.

2. Why does the iron grade in pellets increase after acid leaching? (line24)

3. What is the meaning of the sentence that the the leaching rate of vanadium by salt free roasting is low? (line52）

4. Why and how to control the pellet at 100g ± 1g? (line96)

5. What does damage rate rate mean and define its function? (line340)

Author Response

Thanks for your comments, we have revised this manuscript according to your request.

Author Response File: Author Response.docx

Reviewer 2 Report

The presented article concerns a significant problem of vanadium recovery from ore with relatively low vanadium content. The literature study does not require improvement from the substantive side. However, the description of the research methodology and the development of the results require very significant changes. In addition, significant changes are required on the language side, which in many cases is unacceptable.

Detailed notes:

Line 85: What does "the pellets with good morphology" mean? What was the criterion for selecting pellets?

Line 94 ff: I think it should be leaching efficiency, not leaching rate.

Lines 102-103: No description of compressive strength testing. How many tests have been conducted? What is the measurement error?

Lines 104-105: No description of the porosity test. What is the measurement error?

Lines 118-119: What were the sizes of the pellets taken for testing? This affects the test results.

Line 121: What is falling strength? Please describe the test. Maybe it's a drop test. What is the measurement error?

Line 140: How was bursting temperature determined?

Lines 152-160: Pellet formation time affects pellet size. How was it included? These results don't make much sense.

Line 165: Why temperature gradient and not just temperature? Were the pellets heated with the furnace or placed at a set temperature?

Line 166 onwards: Not baking time but roasting time.

Lines 169-175: How many tests were made for a single point? What is the compressive strength determination error? Were the pellets the same size?

Line 180: What silicate?

Lines 188-189: What new inclusions?

Lines 198-200: The second sentence contradicts the first.

Line 201: Instead of "vanadium is oxidized more thoroughly" maybe it should be "the oxidation state of vanadium increases".

Lines 202-205: Total chaos, not sure what the author meant.

Line 224: Poorly justified choice of bentonite additive. Why 0.8%?

Fig. 7 a-d: Provide other parameters with which the given relationship is shown.

Reactions (12)-(14): No reference in the text.

Fig. 9: The relationships shown are highly debatable and unreliable. The test is very subjective.

Author Response

Thanks for your comments, we have revised this manuscript according to your request.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The following comments have not been taken into account in the amended text:

Lines 105-108: No description of compressive strength testing. How many tests have been conducted? What is the measurement error? No description of the porosity test. What is the measurement error? Comments on the methodology should be answered in the text.

Lines 121-122: What were the sizes of the pellets taken for testing? This affects the test results. Applies to pellet tests (results in Fig. 3). No marking errors. After all, no tests were done on one pellet.

Line 126: What is falling strength? Please describe the test. Maybe it's a drop test. What is the measurement error? Please add the description that is in the answer.

Line 143: How was bursting temperature determined? Please add the description that is in the answer.

Lines 168-169: Can't be added: The pellets are heated together with the furnace.

Lines 172-176: Describe the method of conducting the tests and mark the measurement deviations in Fig. 4. The lack of marking of measurement errors in the drawings is a significant shortcoming in the research work.

Author Response

Dear Sir，
We have made changes in the manuscript regarding your review comments, thank you very much. Please see the attachment

Author Response File: Author Response.docx