Review Reports

Round 1

Reviewer 1 Report

The authors have presented a manuscript detailing the investigation of precipitant matter on the AMD treatment facility at the Daedeok mine.

The following minor comments are highlighted in relation to wording, typos and spelling:

1. Line 69 - typo, components is spelled as omponents.
2. Line 72 - Authors refer to D mine, this is the first instance of the name of the mine and it should be written out in full.
3. Type line 117 - the notation should be '(c)'
4. Typo line 170 - H2O, number '2' should be small subscript
5. Line 202 - 'water continuously flew' should be 'continuously flows'.
6. Line 290 - 'relatively lowing' should be 'relatively lowering'.

The following moderate comments are highlighted related to the content presented in the manuscript.

1. Chapter 1 Introduction: It is not clear what the motivation for this study is and what the contribution of this work is to the wider scientific literature on AMD treatment. What is the research gap being addressed? How is the research novel? This needs to be included in the introduction.
2. Chapter 3 Results: There is no explanation given for the reduction in concentration of potassium from 13 mg/l to 3mg/l. Explanation should be given for this observation like it has been done for other observations.
3. Chapter 4 conclusion: The conclusion chapter does not highlight the significance of the findings. The authors should include a section on how the research findings contribute to the existing body of knowledge on gypsum precipitation in sedimentation treatment of AMD.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

Dear author, my questions as follows:

Line 19. The pH was neutralized…. A pH 9 is alkaline not neutral.

Line 21. Ca and SO₄ is incorrect. They have charges.

Line 23. Correct the name of analysis

Line 25. Indicate sulfate and calcium with their respective charges.

Line 26-27. In the pH range, but I think “neutralization” is not correct.

Line 29. Fe is total iron, or it is ferric or ferrous ion?

Line 43-45. Add more references. You indicate “many countries”, please complement with more literature or studies.

Equation 1 and 2. Include references.

Line 51. Ca is Ca2+

Line 60. Put the charge to sulfate ion.

Line 70. Change “the chemical cost” is reagent costs, production costs.

Line 73-74. Put the respective charges to the ions.

About the process of scale production. Was it completely reproduced in lab?... under the same conditions.

Line 108. Correct pH.

Line 113. You indicate in line 112 the cation analysis and then put all cations without charges.

Line 118. Indicate the name of the techniques.

Line 123. Include the charges.

Line 124. Correct the line.

Line 126. Correct the line

Line 121. Correct the line.

Line 142. Use the equation’s editor.

Lines 149-154, Correct the charges in ions.

Line 168. Put the charge of Mg ions.

Lines 171 to 178. Include the charge.

Check all document and correct the charge of cations.

Put the author contributions in the format of the journal.

Can you extrapolate the results for the general cases of treatment plants?

I think that the manuscript is very general, and the application is too limited. How can you asseverate the reproducibility of your experiments in other treatment plants?

 

 

 

 

Comments for author File: Comments.docx

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

In water treatment, pH of treated water is one of most important element.

Because, I think that it is need to protect the environment of discharge area.

This manuscript has some important results for readers.

However, there are some of changes for the better manuscript.

Please check the comments.

 

1.line 108 to 119 in page 3 and figure 1

I suggest to authors that some details needed about AMD treatment facility for readers.

How long is the precipitation time in sedimentation basin?

 How much is the size of basin(2)?

What is the condition of the sample, “Neutralized water”? How much time has passed after mixed with hydrated lime?

 

2.figure 2 in page 3

It is difficult to understand plot type for Mg and K in graph.

I recommend authors to change the type of them.

 

3.line 138 to 143 in page 4 and figure 3 in page 5

Mineral saturation is 5 in raw water condition at figure 3.

It is easy to generate gypsum in this condition?

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Dear authors,

I detect several mistakes in the text as pH with “P”, punctuation errors, and others.

The methodology, and the number of samples, for example, can be indicated. I don’t see a statistical analysis.

Indicate more references in the introduction section and discussion.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf