Calcined Coal Gangue Fines as the Substitute for Slag in the Production of Alkali-Activated Cements and Its Mechanism

Round 1

Reviewer 1 Report

The paper analyses the utilisation of calcined coal gangue fines (CGF) as a partial substitution of ground granulated blast furnace slag to prepare alkali activated so-called slag materials (AASM). The paper is of interest and can be published. It needs however some corrective actions mainly because the cementitious materials analysed are well-known as alkali activated cements or geopolymers whereas the authors denoted them as AASM.

The comments to be accounted on revision are as follows:

1. The AASM which authors obtained are in reality typical alkali-activated cements abbreviated as AAC – see the classification of AAC by C. Shi and A. Fernandez-Jimenez in Journal of Hazardous Materials, B137, 1656-1663 (2006) doi:10.1016/j.jhazmat.2006.05.008 and/or Chapter 4.1 of monograph R.O. Abdel Rahman et al., Cementitious materials for nuclear waste immobilisation., 258 p., Wiley, Chichester (2015). Correspondingly the authors are invited to use the widely used term of this material – alkali-activated cement (AAC) aiming to stay consistent with works published in the area of materials science. The abbreviation used AASM shall be replaced everywhere by AAC.

2. The title of paper shall contain explicit “alkali activated cements” instead of “alkali activated slag materials”.

3. Lines 47 and 59: define the abbreviation of CGF in the line 47 where it is its first use, and then use it as an abbreviation in the line 59.

4. Lines 61-66 and after: Please note that the calcination of kaolinite results in a material termed metakaolin – see the above references provided. Correspondingly the authors shall use this terminology.

5. Line 79: please explain the granulometric difference between calcined CGF and slag. Is the slag the same as ground granulated blast furnace slag? Explain the source of slag and its physical and chemical properties, its use in production of AAC.

6. Line 96: The calcined CGF in the Table 1 shall be termed metakaolin.

7. Line 99: The text under Fig. 1 shall contain the wording “ground granulated blast furnace slag” rather than just slag. Otherwise please explain the differences.

8. Line 101: same as above.

9. Line 103: The calcined CGF shall be termed metakaolin.

10. Line 107: The calcined CGF shall be termed metakaolin and the slag replaced by ground granulated blast furnace slag.

11. Line 116: The CGF800oC shall be termed metakaolin.

12. Line 164, 182, 206229, 248: Carefully use the abbreviation AAC not AASM as well as in the corresponding texts of manuscript.

The paper can be published on proper account of all above comments. 

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear editor, I send the attached manuscript file with my comments.

 

Sincerely!

 

Adhimar

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Authors forgot (actually ignored) to refer to classification scheme and definition of of AAC's - see the references in the first round report of reviewer: "...see the classification of AAC by C. Shi and A. Fernandez-Jimenez in Journal of Hazardous Materials, B137, 1656-1663 (2006) doi:10.1016/j.jhazmat.2006.05.008 + R.O. Abdel Rahman et al., Cementitious materials for nuclear waste immobilisation., 258 p., Wiley, Chichester (2015)......"

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

The author has made all necessary changes. With that, I recommend that the manuscript be accepted.

Author Response

Dear reviewer,

 

Thank you very much for your approval of the paper.

 

Best regards.

Chenxu Liu

31/7/2022