Strong Structure Formation of Ceramic Composites Based on Coal Mining Overburden Rocks
and Pavel Kozlov 4,*
Round 1
Reviewer 1 Report
1. In the introduction, more contents focus on the important of this work. The literature review of the subject should be added in the introduction to emphasize the innovation of this work.
2. The experimental techniques appear sound and the data are self-consistent. However, the model, manufactory and country of the detection equipment (X-ray powder diffractometry, infrared absorption spectroscopy, scanning electron micros-copy, quartz dilatometry, etc.) should be given.
3. What is the evidence to propose that expediency of firing products from ar-gillites to the maximum temperature of about 975-1025 °С in conditions of the burning of organic substances with the formation of minerals contributes to the formation of ceramic shards?
4. The surveyor's rod should be given in microphotographs in Fig.11.
It is very well-written, and makes for a great read.
Author Response
Response to Reviewer 1 Comments
Point 1: In the introduction, more contents focus on the importance of this work. The literature review of the subject should be added in the introduction to emphasize the innovation of this work.
Response 1: Revised to reflect the comment
Point 2: The experimental techniques appear sound and the data are self-consistent. However, the model, manufactory, and country of the detection equipment (X-ray powder diffractometry, infrared absorption spectroscopy, scanning electron micrmicroscopyartz dilatometry, etc.) should be given.
Response 2: The studies were carried out at the Karaganda Technical University in Karaganda (Kazakhstan) and the Siberian State Industrial University in Novokuznetsk (Russia). The study of the particle size distribution was carried out by a sieve method of analysis, as well as by a laser particle size analyzer Malvern Mastersizer 2000 (UK). Particle measurements were carried out in wet and dry types in the range from 0.02 to 2000 microns. The chemical composition of the starting materials was determined by qualitative spectral analysis on a Shimadzu XRF-1800 X-ray fluorescence wave dispersive spectrometer (Japan). For research of parameters of structure and phase composition of raw components and fired ceramic products the complex of precision and direct methods, including qualitative X-ray diffraction analysis on diffractometer DRON-3. 0 (Russia), X-ray diffraction analysis on X-ray diffractometer Shimadzu XRD-6000 (Japan), differential thermal analysis and thermogravimetry on simultaneous thermal analysis unit Setaram LabSys Evo (France), infrared spectroscopy on spectrophotometer Shimadzu IRAfinity-1 (Japan), optical and electron microscopy using Olympus GX-51 optical microscope with polarization attachment (Japan) and JSM-6460LV scanning electron microscope (Japan) with the system of energy dispersive microanalysis Oxford INCA Energy (UK)..
Point 3: What is the evidence to propose that expediency of firing products from argillites to the maximum temperature of about 975-1025 °С in conditions of the burning of organic substances with the formation of minerals contributes to the formation of ceramic shards?
Response 3: According to the results of the research, the following optimal firing regime was adopted: the rate of temperature rise 100 deg/h, up to 800 ° C, and 20 deg/h, up to a maximum temperature of 1000 ° C. The duration of isothermal soaking at the maximum temperature is 2 hours. The model was adopted based on experimental studies and calculations, taking into account the control of all firing stages. As well as X-ray phase and other studies, physical and mechanical tests of samples after firing. The newly formed minerals mullite, cristobalite, and hematite are fixed on the X-ray images. It is at this temperature that optimal sintering takes place, organic substances burn out completely, and strength and cold-resistance grades are ensured. The model has been tested and confirmed in factory conditions.
Point 4: The surveyor's rod should be given in microphotographs in Fig.11.
Response 4: Revised to reflect the comment
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors studied the properties of raw materials and the processes of structure formation based on overburdened rocks of coal mining and additives. The results showed that the use of highly mineralized carbonaceous rocks as solid additives provides the increase of the strength of the product in 2-2.5 times. Research results prove that the composition and properties of overburdened rocks of coal mining are close to conventional clays. With special technological preparation, they can be used for the production of composite ceramic products.
The reviewers make the following recommendations.
1. How stable is the composition of the selected raw material? Please explain.
2. The microstructure of ceramic tile has a direct effect on the performance. How to control the microstructure of each batch of ceramic tile?
Author Response
Response to Reviewer 2 Comments
Point 1: The authors studied the properties of raw materials and the processes of structure formation based on overburdened rocks of coal mining and additives. The results showed that the use of highly mineralized carbonaceous rocks as solid additives provides an increase in the strength of the product by 2-2.5 times. Research results prove that the composition and properties of overburdened rocks of coal mining are close to conventional clays. With special technological preparation, they can be used for the production of composite ceramic products.
The reviewers make the following recommendations.
- How stable is the composition of the selected raw material? Please explain.
Response 1: Overburden rocks from coal mining as a raw material are not always stable, as well as other clay raw materials. It depends on the lithological type and horizon of the occurrence of rocks. As a result of the studies, it was revealed that the most stable in composition are argillites and siltstones of +100 m horizon. The horizons start from the top of the coal seam. Selective selection of raw materials for use in the production of building ceramics is recommended. Research on the use of correcting additives for the stabilization of properties of raw materials is conducted.
Point 2: The microstructure of ceramic tile has a direct effect on the performance. How to control the microstructure of each batch of ceramic tile?
Response 2: We agree. These studies are conducted mainly for ceramic bricks. Control of the physical and mechanical properties of the finished products is carried out in the conditions of the factory laboratories and certification organizations.
Author Response File: Author Response.docx
Reviewer 3 Report
This study demonstrated the possibility to use coal mining waste as a usable building material by providing various experimental and detailed data. However, in the text, there are several questions and corrections to address as given below.
1. The English in the manuscript should be polished by a native speaker of English or a professional editor, etc.
2. In Table 4, what do the numbers “1”-“8” mean?
3. On p.9, what do you mean by “yi”? Is it miswritten for “xi”?
4. On p.11, line 8, as seen in Table 7, “2.7-8.1%” → “2.7-6.1%”, right?
5. On p.12, line 9-10 from the bottom, the shrinkage occurrence at 7.9 and 7.5% moisture output does not seem to be coincide with Fig.7.
6. In Table 11, “combustion of organic matter” appears twice. They have different meanings or a mistake?
7. On p.20 line 8 and line 6 from the bottom, “75 cycles” and “50-100 cycles” do not seem to be coincide with Table 14.
8. On p.20, on the last paragraph, how do you determine the given firing condition as optimal in this study?
Please see the above comments.
Author Response
Response to Reviewer 3 Comments
Point 1: This study demonstrated the possibility to use coal mining waste as a usable building material by providing various experimental and detailed data. However, in the text, there are several questions and corrections to address as given below.
- The English in the manuscript should be polished by a native speaker of English or a professional editor, etc.
Response 1: Corrected
Point 2: In Table 4, what do the numbers “1”-“8” mean?
Response 2: This is column numbering (deleted)
Point 3: On p.9, what do you mean by “yi”? Is it miswritten for “xi”?
Response 3: This is Xi , (typo) corrected
Point 4: On p.11, line 8, as seen in Table 7, “2.7-8.1%” → “2.7-6.1%”, right?
Response 4: Correct in Table 6.1. ( 8.1 typo) Corrected
Point 5: On p.12, line 9-10 from the bottom, the shrinkage occurrence at 7.9 and
7.5% moisture output does not seem to be coincide with Fig.7.
Response 5: 7.9 and 7.5% is for siltstones. For argillite 9.6 and 10.1 (corrected)
Point 6: In Table 11, “combustion of organic matter” appears twice. They have different meanings or a mistake?
Response 6: They have different meanings. Ignition and combustion of volatile components of a combustible substance is the initial stage of combustion of organic substances.
The combustion of organic matter is the end of the combustion process.
Point 7: On p.20 line 8 and line 6 from the bottom, “75 cycles” and “50-100 cycles” do not seem to be coincide with Table 14.
Response 7: We agree with the comment. Corrected. Individual studies with this raw material, depending on the additives, show a frost resistance of up to 100 cycles or more. In this study, without additives, the frost resistance to 75, (Table 12). With additives 74 cycles (Table 14).
Point 8: On p.20, on the last paragraph, how do you determine the given firing condition as optimal in this study?
Response 8: According to the results of the research, the following optimal firing regime was adopted: the rate of temperature rise 100 deg/h, up to 800 ° C, and 20 deg/h, up to a maximum temperature of 1000 ° C. The duration of isothermal soaking at the maximum temperature is 2 hours.
The model was adopted based on experimental studies and calculations, taking into account the control of all firing stages. As well as X-ray phase and other studies, physical and mechanical tests of samples. The model has been tested and confirmed under factory conditions.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The manuscript has been well revised.
minor modification
Reviewer 2 Report
According to the author's reply and the revision of the manuscript, the reviewer agrees with the author's revision, and the manscript can be published.
Reviewer 3 Report
The revised manuscript is now considered acceptable for publication.
It has been well revised.
